Prevalence of micronuclei in exfoliated uterine cervical cells from patients with risk factors for cervical cancer

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Lízia Maria Franco dos Reis Campos

Full Text Available CONTEXT AND OBJECTIVE: Pap smears are the most common and inexpensive screening method for cervical cancer. We analyzed micronucleus prevalence in exfoliated cervical mucosa cells, to investigate associations between increased numbers of micronuclei and risk factors for cervical cancer. DESIGN AND SETTING: Analytical cross-sectional study, at Instituto de Pesquisa em Oncologia (IPON. METHODS: Exfoliated cervical cells were obtained from 101 patients between September 2004 and November 2005. Patients' ages, habits (passive or active smoking, alcoholism and numbers of sexual partners, age at first sexual intercourse, contraceptive methods used, histories of sexually transmitted diseases, use of hormone replacement therapy, numbers of pregnancies and abortions, inflammatory cytology and cervical intraepithelial neoplasia (CIN were obtained. Cells were collected using Ayre spatulas, transferred to vials containing 0.9% saline solution for micronucleus tests and analyzed at 1000x magnification. The number of micronuclei in 1,000 epithelial cells per patient sample was counted. RESULTS: Comparisons between groups with active (7.9 ± 7.8 and passive (7.2 ± 10.6 smoking versus no smoking (3.7 ± 5.1; with/without alcoholism (7.8 ± 1.4 and 6.9 ± 10.1; with/without inflammatory cytology (10.7 ± 10.5 and 1.3 ± 1.7; and with CIN I, II and III and no CIN (respectively 4.3 ± 4.3, 10.6 ± 5.3, 22.7 ± 11.9 and 1.3 ± 1.4 found elevated micronucleus prevalence (P < 0.05. CONCLUSIONS: We concluded that the prevalence of micronuclei in exfoliated uterine cervical cells was greater in patients with one or more risk factors for uterine cervical cancer than in patients without risk factors.

On the exfoliating polymeric cellular dosage forms for immediate drug release.

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Blaesi, Aron H; Saka, Nannaji

2016-06-01

The most prevalent pharmaceutical dosage forms at present-the oral immediate-release tablets and capsules-are granular solids. Though effective in releasing drug rapidly, development and manufacture of such dosage forms are fraught with difficulties inherent to particulate processing. Predictable dosage form manufacture could be achieved by liquid-based processing, but cast solid dosage forms are not suitable for immediate drug release due to their resistance to fluid percolation. To overcome this limitation, we have recently introduced cellular dosage forms that can be readily prepared from polymeric melts. It has been shown that open-cell structures comprising polyethylene glycol 8000 (PEG 8k) excipient and a drug exfoliate upon immersion in a dissolution medium. The drug is then released rapidly due to the large specific surface area of the exfoliations. In this work, we vary the molecular weight of the PEG excipient and investigate its effect on the drug release kinetics of structures with predominantly open-cell topology. We demonstrate that the exfoliation rate decreases substantially if the excipient molecular weight is increased from 12 to 100kg/mol, which causes the drug dissolution time to increase by more than a factor of ten. A model is then developed to elucidate the exfoliation behavior of cellular structures. Diverse transport processes are considered: percolation due to capillarity, diffusion of dissolution medium through the cell walls, and viscous flow of the saturated excipient. It is found that the lower exfoliation rate and the longer dissolution time of the dosage forms with higher excipient molecular weight are primarily due to the greater viscosity of the cell walls after fluid penetration. Copyright © 2016 Elsevier B.V. All rights reserved.

Water-soluble Microwave-exfoliated Graphene Nanosheet/Platinum Nanoparticle Composite and Its Application in Dye-Sensitized Solar Cells

International Nuclear Information System (INIS)

Zhai, Peng; Chang, Ya-Huei; Huang, Yu-Ting; Wei, Tzu-Chien; Su, Haijun; Feng, Shien-Ping

2014-01-01

In this paper, a facile and scalable aqueous process including mild oxidative intercalation, microwave exfoliation, ultrasonication, drying and Ar-annealing is developed to synthesize the water-soluble microwave-exfoliated graphene (MEG)/platinum nanoparticles (PtNPs) composite, which has a relative low defect level and can be readily dispersed in deionized water without adding surfactants. This low cost synthesis method is applicable in many systems, such as supercapacitors, thermal storage, lithium battery and Dye-sensitized solar cells (DSSCs). An efficiency of 6.69% for the MEG/PtNPs composite deposited on ITO PEN as flexible counter electrode (CE) for DSSCs has been obtained, higher than the control device made by PVP-Pt as flexible CE

Regulation of pulmonary inflammation by mesenchymal cells

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Alkhouri, Hatem; Poppinga, Wilfred Jelco; Tania, Navessa Padma; Ammit, Alaina; Schuliga, Michael

2014-01-01

Pulmonary inflammation and tissue remodelling are common elements of chronic respiratory diseases such as asthma, chronic obstructive pulmonary disease (COPD), idiopathic pulmonary fibrosis (IPF), and pulmonary hypertension (PH). In disease, pulmonary mesenchymal cells not only contribute to tissue

One-step exfoliation and surface modification of lamellar hydroxyapatite by intercalation of glucosamine

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Luo, Honglin [Research Institute for Biomaterials and Transportation, East China Jiaotong University, Nanchang, 330013 (China); School of Materials Science and Engineering, Tianjin University, Tianjin, 300072 (China); Li, Wei; Ji, Dehui [Research Institute for Biomaterials and Transportation, East China Jiaotong University, Nanchang, 330013 (China); Zuo, Guifu [Hebei Provincial Key Laboratory of Inorganic Nonmetallic Materials, College of Materials Science and Engineering, Hebei United University, Tangshan, 063009 (China); Xiong, Guangyao, E-mail: xiongguangyao@163.com [Research Institute for Biomaterials and Transportation, East China Jiaotong University, Nanchang, 330013 (China); Zhu, Yong [School of Chemical Engineering, Tianjin University, Tianjin, 300072 (China); Li, Lili; Han, Ming [Research Institute for Biomaterials and Transportation, East China Jiaotong University, Nanchang, 330013 (China); Wu, Caoqun [School of Materials Science and Engineering, Tianjin University, Tianjin, 300072 (China); Wan, Yizao, E-mail: yzwantju@126.com [Research Institute for Biomaterials and Transportation, East China Jiaotong University, Nanchang, 330013 (China); School of Materials Science and Engineering, Tianjin University, Tianjin, 300072 (China)

2016-04-15

Effective exfoliation is crucial to the application of layered materials in many fields. Herein, we report a novel effective, scalable, and ecofriendly method for the exfoliation of lamellar HAp by glucosamine intercalation such that individual HAp nanoplates can be obtained. The as-exfoliated HAp nanoplates were characterized by Fourier transform infrared (FTIR), X-ray diffraction (XRD), transmission electron microscopy (TEM), and thermogravimetric (TG) analysis. It is found that the glucosamine intercalation not only results in complete exfoliation of lamellar HAp but also introduces the glucosamine molecules onto the surface of individual HAp nanoplates, thus obtaining separated glucosamine-grafted HAp nanoplates (Glu-HAps). Results from MTT assay demonstrate that glucosamine grafting on HAp nanoplates greatly improves the cell growth and proliferation as compared to nongrafted HAp counterparts. - Highlights: • Glucosamine was used as intercalation agent to exfoliate lamellar hydroxyapatite. • Glucosamine was grafted onto the as-exfoliated nanoplate-like hydroxyapatite. • Exfoliation and surface grafting were accomplished in one step. • Glucosamine-grafted HAp showed improved biocompatibility over nongrafted one.

A model for blister exfoliation

International Nuclear Information System (INIS)

Deb, S.K.; Sood, D.K.

1983-01-01

We describe a mechanism for exfoliation of blisters by taking into account the temperature rise of the blister cover due to the incident beam heating. The rise in temperature is calculated by solving the time dependent heat conduction equation. The exfoliation is initiated either by a local melting or by the reduction of material strength due to the temperature rise leading to rupture of the blister skin by the pressure of the gas in the blister cavity. We propose two types of exfoliation: peripheral and non-peripheral, depending on the blister size. This model agrees well with the various experimental results reported on blister exfoliation. It is argued that this thermally assisted exfoliation of blisters may render the first wall erosion by high energy helium flux more serious than considered hitherto, in an actual fusion reactor system. (author)

Ultrastructural analysis of oral exfoliated epithelial cells of tobacco smokers and betel nut chewers: A scanning electron microscopy study.

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Khan, Sameera Shamim; Shreedhar, Balasundari; Kamboj, Mala

2016-01-01

The study was undertaken to correlate epithelial surface pattern changes of oral exfoliated cells of tobacco smokers and betel nut chewers and also to compare them with patients of oral squamous cell carcinoma (OSCC) and healthy individuals. In this cross-sectional study, a total of fifty persons were included in the study, out of which thirty formed the study group (15 each tobacco smokers and betel nut chewers) and twenty formed the control group (ten each of OSCC patients - positive control and ten normal buccal mucosa - negative control). Their oral exfoliated cells were scraped, fixed, and studied under scanning electron microscope (SEM). The statistical analysis was determined using ANOVA, Tukey honestly significant difference, Chi-square test, and statistical SPASS software, P betel nut chewers compared to normal oral mucosa have been tabulated. In normal oral mucosa, cell surface morphology depends on the state of keratinization of the tissue. Thus, it could prove helpful in detecting any carcinomatous change at its incipient stage and also give an insight into the ultra-structural details of cellular differentiations in epithelial tissues.

Speciation of arsenic in exfoliated urinary bladder epithelial cells from individuals exposed to arsenic in drinking water

Czech Academy of Sciences Publication Activity Database

Hernández-Zavala, A.; Valenzuela, O.L.; Matoušek, Tomáš; Drobná, Z.; Dědina, Jiří; Garcia-Vargas, G.G.; Thomas, D. J.; Del Razo, L.M.; Stýblo, M.

2008-01-01

Roč. 116, č. 12 (2008), s. 1656-1660 ISSN 0091-6765 R&D Projects: GA AV ČR IAA400310507 Institutional research plan: CEZ:AV0Z40310501 Keywords : arsenic species * drinking water * exfoliated human urinary bladder epithelial cells Subject RIV: CB - Analytical Chemistry, Separation Impact factor: 6.123, year: 2008

Thermal influences on spontaneous rock dome exfoliation

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Collins, Brian D.; Stock, Greg M.; Eppes, Martha C.; Lewis, Scott W.; Corbett, Skye C.; Smith, Joel B.

2018-01-01

Rock domes, with their onion-skin layers of exfoliation sheets, are among the most captivating landforms on Earth. Long recognized as integral in shaping domes, the exact mechanism(s) by which exfoliation occurs remains enigmatic, mainly due to the lack of direct observations of natural events. In August 2014, during the hottest days of summer, a granitic dome in California, USA, spontaneously exfoliated; witnesses observed extensive cracking, including a ~8000 kg sheet popping into the air. Subsequent exfoliation episodes during the following two summers were recorded by instrumentation that captured—for the first time—exfoliation deformation and stress conditions. Here we show that thermal cycling and cumulative dome surface heating can induce subcritical cracking that culminates in seemingly spontaneous exfoliation. Our results indicate that thermal stresses—largely discounted in dome formation literature—can play a key role in triggering exfoliation and therefore may be an important control for shaping domes worldwide.

Thermally exfoliated graphite oxide

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Prud'Homme, Robert K. (Inventor); Aksay, Ilhan A. (Inventor); Abdala, Ahmed (Inventor)

2011-01-01

A modified graphite oxide material contains a thermally exfoliated graphite oxide with a surface area of from about 300 sq m/g to 2600 sq m/g, wherein the thermally exfoliated graphite oxide displays no signature of the original graphite and/or graphite oxide, as determined by X-ray diffraction.

Raman exfoliative cytology for oral precancer diagnosis

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Sahu, Aditi; Gera, Poonam; Pai, Venkatesh; Dubey, Abhishek; Tyagi, Gunjan; Waghmare, Mandavi; Pagare, Sandeep; Mahimkar, Manoj; Murali Krishna, C.

2017-11-01

Oral premalignant lesions (OPLs) such as leukoplakia, erythroplakia, and oral submucous fibrosis, often precede oral cancer. Screening and management of these premalignant conditions can improve prognosis. Raman spectroscopy has previously demonstrated potential in the diagnosis of oral premalignant conditions (in vivo), detected viral infection, and identified cancer in both oral and cervical exfoliated cells (ex vivo). The potential of Raman exfoliative cytology (REC) in identifying premalignant conditions was investigated. Oral exfoliated samples were collected from healthy volunteers (n=20), healthy volunteers with tobacco habits (n=20), and oral premalignant conditions (n=27, OPL) using Cytobrush. Spectra were acquired using Raman microprobe. Spectral acquisition parameters were: λex: 785 nm, laser power: 40 mW, acquisition time: 15 s, and average: 3. Postspectral acquisition, cell pellet was subjected to Pap staining. Multivariate analysis was carried out using principal component analysis and principal component-linear discriminant analysis using both spectra- and patient-wise approaches in three- and two-group models. OPLs could be identified with ˜77% (spectra-wise) and ˜70% (patient-wise) sensitivity in the three-group model while with 86% (spectra-wise) and 83% (patient-wise) in the two-group model. Use of histopathologically confirmed premalignant cases and better sampling devices may help in development of improved standard models and also enhance the sensitivity of the method. Future longitudinal studies can help validate potential of REC in screening and monitoring high-risk populations and prognosis prediction of premalignant lesions.

Chromosomal Damage and Apoptosis in Exfoliated Buccal Cells from Individuals with Oral Cancer

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Dórea, Lavínia Tércia Magalhães; Meireles, José Roberto Cardoso; Lessa, Júlia Paula Ramos; Oliveira, Márcio Campos; de Bragança Pereira, Carlos Alberto; Polpo de Campos, Adriano; Cerqueira, Eneida de Moraes Macílio

2012-01-01

This study aimed to investigate cytological abnormalities indicative of chromosome damage (micronuclei) and apoptosis (karyorrhexis, pyknosis, and condensed chromatin) in exfoliated cells from the buccal mucosa of patients with oral cancer and control subjects. The sample included twenty individuals with oral cancer and forty individuals with normal buccal mucosa. Material was collected from the cheek epithelium in areas with lesions and areas without abnormalities. A minimum of one thousand cells was analyzed. Micronuclei were found significantly more frequently in cells collected from lesions than in cells from normal areas, independent of the presence/absence of cancer (P < 0.0001). They were also significantly more frequent in smokers and in mouthwash users (P < 0.0001). Apoptosis occurred significantly less frequently in individuals with oral cancer (P < 0.0001). These results show that oral cancer is associated with higher frequency of chromosomal damage and suggest that apoptosis is compromised in the buccal cells of individuals with this kind of neoplasia. PMID:22315605

Pulmonary langerhans cell histiocytosis

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Suri Harpreet S

2012-03-01

Full Text Available Abstract Pulmonary Langerhans Cell Histiocytosis (PLCH is a relatively uncommon lung disease that generally, but not invariably, occurs in cigarette smokers. The pathologic hallmark of PLCH is the accumulation of Langerhans and other inflammatory cells in small airways, resulting in the formation of nodular inflammatory lesions. While the overwhelming majority of patients are smokers, mechanisms by which smoking induces this disease are not known, but likely involve a combination of events resulting in enhanced recruitment and activation of Langerhans cells in small airways. Bronchiolar inflammation may be accompanied by variable lung interstitial and vascular involvement. While cellular inflammation is prominent in early disease, more advanced stages are characterized by cystic lung destruction, cicatricial scarring of airways, and pulmonary vascular remodeling. Pulmonary function is frequently abnormal at presentation. Imaging of the chest with high resolution chest CT scanning may show characteristic nodular and cystic abnormalities. Lung biopsy is necessary for a definitive diagnosis, although may not be required in instances were imaging findings are highly characteristic. There is no general consensus regarding the role of immunosuppressive therapy in smokers with PLCH. All smokers must be counseled on the importance of smoking cessation, which may result in regression of disease and obviate the need for systemic immunosuppressive therapy. The prognosis for most patients is relatively good, particularly if longitudinal lung function testing shows stability. Complications like pneumothoraces and secondary pulmonary hypertension may shorten life expectancy. Patients with progressive disease may require lung transplantation.

Formation of Exfoliation Joints

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Martel, S. J.

2004-12-01

The Earth's internal stresses interact with the topographic surface to affect many phenomena. Exfoliation joints, or sheeting joints, are widespread manifestations of this interaction. These opening-mode fractures form subparallel to the Earth's surface, bounding roughly concentric slabs of rock that resemble the layers of an onion. They occur worldwide in all major bedrock types, attain in-plane dimensions of hundreds of meters, exert a strong influence on groundwater flow, and help produce spectacular scenery, as in Yosemite National Park. The mechanism that causes them has been enigmatic. They are widely regarded as forming in response to "removal of overburden", but large fractures do not open in rocks merely by relieving a compressive stress. High fluid pressures, thermal effects, rock heterogeneity, and weathering also are rejected as primary causes of these fractures. Tensile stresses normal to the surface are required for large exfoliation fractures to open. Intriguingly, high surface-parallel compressive stresses are widely documented where exfoliation joints occur. Both numerical and analytical solutions for two-dimensional elastic bodies show that localized tensile stresses perpendicular to the ground surface must develop beneath certain topographies subject to strong compressive stresses parallel to the surface. This highly non-intuitive effect reflects the profound influence that topography can have on stresses near the surface of the Earth, and it can explain how exfoliation joints open. The theoretical results also indicate that exfoliation joint distributions could be used to infer the horizontal stresses near the Earth's surface.

Progenitor cells in pulmonary vascular remodeling

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Yeager, Michael E.; Frid, Maria G.; Stenmark, Kurt R.

2011-01-01

Pulmonary hypertension is characterized by cellular and structural changes in the walls of pulmonary arteries. Intimal thickening and fibrosis, medial hypertrophy and fibroproliferative changes in the adventitia are commonly observed, as is the extension of smooth muscle into the previously non-muscularized vessels. A majority of these changes are associated with the enhanced presence of α-SM-actin+ cells and inflammatory cells. Atypical abundances of functionally distinct endothelial cells, particularly in the intima (plexiform lesions), and also in the perivascular regions, are also described. At present, neither the origin(s) of these cells nor the molecular mechanisms responsible for their accumulation, in any of the three compartments of the vessel wall, have been fully elucidated. The possibility that they arise from either resident vascular progenitors or bone marrow–derived progenitor cells is now well established. Resident vascular progenitor cells have been demonstrated to exist within the vessel wall, and in response to certain stimuli, to expand and express myofibroblastic, endothelial or even hematopoietic markers. Bone marrow–derived or circulating progenitor cells have also been shown to be recruited to sites of vascular injury and to assume both endothelial and SM-like phenotypes. Here, we review the data supporting the contributory role of vascular progenitors (including endothelial progenitor cells, smooth muscle progenitor cells, pericytes, and fibrocytes) in vascular remodeling. A more complete understanding of the processes by which progenitor cells modulate pulmonary vascular remodeling will undoubtedly herald a renaissance of therapies extending beyond the control of vascular tonicity and reduction of pulmonary artery pressure. PMID:22034593

Sickle Cell Disease and Pulmonary Hypertension

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... My doctor wants to screen me for pulmonary hypertension. Why is this? Sickle cell disease (SCD), a ... What are some of the symptoms of pulmonary hypertension? Because they are somewhat general symptoms, the characteristics ...

Exfoliative liver cytology in Oreochromis mossambicus as a bio ...

African Journals Online (AJOL)

The use of exfoliative cytology as a bio-assessment tool was evaluated to (1) identify and describe different cell types of normal liver cytology of Oreochromis mossambicus, (2) identify and describe changes in the cell types after exposure to cadmium and zinc, and (3) determine if non-imaging-guided fine-needle aspiration ...

Role of imprint/exfoliative cytology in ulcerated skin neoplasms.

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Ramakrishnaiah, Vishnu Prasad Nelamangala; Babu, Ravindra; Pai, Dinker; Verma, Surendra Kumar

2013-12-01

Imprint cytology is a method of studying cells by taking an imprint from the cut surface of a wedge biopsy specimen or from the resected margins of a surgical specimen. It is rapid, simple and fairly accurate. Exfoliative cytology is an offshoot from the imprint cytology where in cells obtained from the surface of ulcers, either by scrape or brush, are analyzed for the presence of malignant cells. We undertook this study to see the role of imprint/exfoliative cytology in the diagnosis of ulcerated skin neoplasm and to check the adequacy of resected margins intra-operatively. This was a prospective investigative study conducted from September 2003 to July 2005. All patients presenting to surgical clinic with ulcerated skin and soft tissue tumours were included in the study. A wedge biopsy obtained from the ulcer and imprint smears were taken from the cut surface. Exfoliative cytology was analyzed from the surface smears. Wedge biopsy specimen was sent for histopathological (HPE) examination. The cytology and HPE were analyzed by a separate pathologist. Imprint cytology was also used to check the adequacy of resected margins in case of wide excision. This was compared with final HPE. Total of 107 patients was included in the present study and 474 imprint smears were done, with an average of 4.43 slides per lesion. Out of 59 wide excision samples, 132 imprint smears were prepared for assessing resected margins accounting for an average of 2.24 slides per each excised lesion. On combining imprint cytology with exfoliative cytology the overall sensitivity, specificity and positive predictive value were 90.38 %, 100 % and 90.38 % respectively. Only one out of 59 cases had a positive resected margin which was not picked by imprint cytology. Imprint cytology can be used for rapid and accurate diagnosis of various skin malignancies. It can also be used to check the adequacy of the resected margin intraoperatively.

Edge orientations of mechanically exfoliated anisotropic two-dimensional materials

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Yang, Juntan; Wang, Yi; Li, Yinfeng; Gao, Huajian; Chai, Yang; Yao, Haimin

2018-03-01

Mechanical exfoliation is an approach widely applied to prepare high-quality two-dimensional (2D) materials for investigating their intrinsic physical properties. During mechanical exfoliation, in-plane cleavage results in new edges whose orientations play an important role in determining the properties of the as-exfoliated 2D materials especially those with high anisotropy. Here, we systematically investigate the factors affecting the edge orientation of 2D materials obtained by mechanical exfoliation. Our theoretical study manifests that the fractured direction during mechanical exfoliation is determined synergistically by the tearing direction and material anisotropy of fracture energy. For a specific 2D material, our theory enables us to predict the possible edge orientations of the exfoliated flakes as well as their occurring probabilities. The theoretical prediction is experimentally verified by examining the inter-edge angles of the exfoliated flakes of four typical 2D materials including graphene, MoS2, PtS2, and black phosphorus. This work not only sheds light on the mechanics of exfoliation of the 2D materials but also provides a new approach to deriving information of edge orientations of mechanically exfoliated 2D materials by data mining of their macroscopic geometric features.

Oxidative stress induced pulmonary endothelial cell proliferation is ...

African Journals Online (AJOL)

Cellular hyper-proliferation, endothelial dysfunction and oxidative stress are hallmarks of the pathobiology of pulmonary hypertension. Indeed, pulmonary endothelial cells proliferation is susceptible to redox state modulation. Some studies suggest that superoxide stimulates endothelial cell proliferation while others have ...

Exfoliation syndrome in Northern Nigeria

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Idakwo U

2018-01-01

Full Text Available Ugbede Idakwo,1 Olusola Olawoye,2 Benedictus GK Ajayi,1 Robert Ritch3 1Eleta Eye Institute, Ibadan, Nigeria; 2Department of Ophthalmology, College of Medicine, University of Ibadan, Ibadan, Nigeria; 3Einhorn Clinical Research Center, Department of Ophthalmology, New York Eye and Ear Infirmary of Mount Sinai, New York, NY, USA Purpose: To estimate the frequency of exfoliation syndrome (XFS and its association with ocular diseases in Northern Nigeria.Materials and methods: Consecutive patients who presented to the outpatient department of ECWA Eye Hospital Kano from February 2015 to May 2015 were included in the study. Each patient had a complete ophthalmic examination. The anterior segment examination included tonometry, gonioscopy, and detailed slit-lamp examination to assess for the presence or absence of exfoliation material, inflammatory cells, and other abnormal findings. Patients with exfoliation material on the anterior lens surface and/or pupillary margin in either or both eyes were considered to have XFS. Statistical analysis was performed using the Statistical Package for the Social Sciences version 16.0.Results: A total of 620 patients living in Northern Nigeria from the 6 geopolitical zones were examined. The majority of them (34.5% were indigenous Hausas. There was a male preponderance of 56.6%, while the mean age at presentation for examination in all age groups was 55.7±13.7 years. There were 9 patients with XFS; the frequency was 1.5%, with most of the patients being 70–80 years old. In patients who were ≥50 years, the frequency was 2.5%. Patients with XFS had a higher mean age of 68±4.9 years. The frequency of XFS among glaucoma patients was 4.4%, while among cataract patients it was 3.7%. No other associated ocular disease was found in the patients with XFS.Conclusion: This study shows that XFS does exist in Northern Nigeria, as was found in the South. The prevalence of XFS was, however, not reported in the Nigerian

Hypoxia-induced glucose-6-phosphate dehydrogenase overexpression and -activation in pulmonary artery smooth muscle cells: implication in pulmonary hypertension

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Chettimada, Sukrutha; Gupte, Rakhee; Rawat, Dhwajbahadur; Gebb, Sarah A.; McMurtry, Ivan F.

2014-01-01

Severe pulmonary hypertension is a debilitating disease with an alarmingly low 5-yr life expectancy. Hypoxia, one of the causes of pulmonary hypertension, elicits constriction and remodeling of the pulmonary arteries. We now know that pulmonary arterial remodeling is a consequence of hyperplasia and hypertrophy of pulmonary artery smooth muscle (PASM), endothelial, myofibroblast, and stem cells. However, our knowledge about the mechanisms that cause these cells to proliferate and hypertrophy in response to hypoxic stimuli is still incomplete, and, hence, the treatment for severe pulmonary arterial hypertension is inadequate. Here we demonstrate that the activity and expression of glucose-6-phosphate dehydrogenase (G6PD), the rate-limiting enzyme of the pentose phosphate pathway, are increased in hypoxic PASM cells and in lungs of chronic hypoxic rats. G6PD overexpression and -activation is stimulated by H2O2. Increased G6PD activity contributes to PASM cell proliferation by increasing Sp1 and hypoxia-inducible factor 1α (HIF-1α), which directs the cells to synthesize less contractile (myocardin and SM22α) and more proliferative (cyclin A and phospho-histone H3) proteins. G6PD inhibition with dehydroepiandrosterone increased myocardin expression in remodeled pulmonary arteries of moderate and severe pulmonary hypertensive rats. These observations suggest that altered glucose metabolism and G6PD overactivation play a key role in switching the PASM cells from the contractile to synthetic phenotype by increasing Sp1 and HIF-1α, which suppresses myocardin, a key cofactor that maintains smooth muscle cell in contractile state, and increasing hypoxia-induced PASM cell growth, and hence contribute to pulmonary arterial remodeling and pathogenesis of pulmonary hypertension. PMID:25480333

Granite Exfoliation, Cosumnes River Watershed, Somerset, California

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Crockett, I. Q.; Neiss-Cortez, M.

2015-12-01

In the Sierra Nevada foothills of California there are many exposed granite plutons within the greater Sierra Nevada batholith. As with most exposed parts of the batholith, these granite slabs exfoliate. It is important to understand exfoliation for issues of public safety as it can cause rock slides near homes, roads, and recreation areas. Through observation, measuring, and mapping we characterize exfoliation in our Cosumnes River watershed community.

Computer-assisted diagnostic tool to quantify the pulmonary veins in sickle cell associated pulmonary hypertension

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Jajamovich, Guido H.; Pamulapati, Vivek; Alam, Shoaib; Mehari, Alem; Kato, Gregory J.; Wood, Bradford J.; Linguraru, Marius George

2012-03-01

Pulmonary hypertension is a common cause of death among patients with sickle cell disease. This study investigates the use of pulmonary vein analysis to assist the diagnosis of pulmonary hypertension non-invasively with CT-Angiography images. The characterization of the pulmonary veins from CT presents two main challenges. Firstly, the number of pulmonary veins is unknown a priori and secondly, the contrast material is degraded when reaching the pulmonary veins, making the edges of these vessels to appear faint. Each image is first denoised and a fast marching approach is used to segment the left atrium and pulmonary veins. Afterward, a geodesic active contour is employed to isolate the left atrium. A thinning technique is then used to extract the skeleton of the atrium and the veins. The locations of the pulmonary veins ostia are determined by the intersection of the skeleton and the contour of the atrium. The diameters of the pulmonary veins are measured in each vein at fixed distances from the corresponding ostium, and for each distance, the sum of the diameters of all the veins is computed. These indicators are shown to be significantly larger in sickle-cell patients with pulmonary hypertension as compared to controls (p-values < 0.01).

Characterization of cloned cells from an immortalized fetal pulmonary type II cell line

Energy Technology Data Exchange (ETDEWEB)

Henderson, R.F.; Waide, J.J.; Lechner, J.F.

1995-12-01

A cultured cell line that maintained expression of pulmonary type II cell markers of differentiation would be advantageous to generate a large number of homogenous cells in which to study the biochemical functions of type II cells. Type II epithelial cells are the source of pulmonary surfactant and a cell of origin for pulmonary adenomas. Last year our laboratory reported the induction of expression of two phenotypic markers of pulmonary type II cells (alkaline phosphatase activity and surfactant lipid synthesis) in cultured fetal rat lung epithelial (FRLE) cells, a spontaneously immortalized cell line of fetal rat lung type II cell origin. Subsequently, the induction of the ability to synthesize surfactant lipid became difficult to repeat. We hypothesized that the cell line was heterogenuous and some cells were more like type II cells than others. The purpose of this study was to test this hypothesis and to obtain a cultured cell line with type II cell phenotypic markers by cloning several FRLE cells and characterizing them for phenotypic markers of type II cells (alkaline phosphatase activity and presence of surfactant lipids). Thirty cloned cell lines were analyzed for induced alkaline phosphatase activity (on x-axis) and for percent of phospholipids that were disaturated (i.e., surfactant).

Is mobile phone radiation genotoxic? An analysis of micronucleus frequency in exfoliated buccal cells.

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de Oliveira, F M; Carmona, A M; Ladeira, C

2017-10-01

Electromagnetic fields (EMF) are classified as "possibly carcinogenic" by the International Agency for Research on Cancer (IARC). Some publications have reported associations between EMF exposure and DNA damage, but many other studies contradict such findings. Cytomorphological changes, such as micronuclei (MN), indicative of genomic damage, are biomarkers of genotoxicity. To test whether mobile phone-associated EMF exposure affects the MN frequency in exfoliated buccal cells, we obtained cells smears from the left and right inner cheeks of healthy mobile phone users, aged 18-30 (n=86), who also completed a characterization survey. MN frequencies were tested for potential confounding factors and for duration of phone use and preferential side of mobile phone use. No relationship was observed between MN frequency and duration of mobile phone use in daily calls. Cells ipsilateral to mobile phone use did not present a statistically significantly higher MN frequency, compared to cells contralateral to exposure. A highly statistically significant (pphone-associated EMF do not to induce MN formation in buccal cells at the observed exposure levels. Copyright © 2017 Elsevier B.V. All rights reserved.

Functional live cell imaging of the pulmonary neuroepithelial body microenvironment

NARCIS (Netherlands)

De Proost, Ian; Pintelon, Isabel; Brouns, Inge; Kroese, A; Riccardi, Daniela; Kemp, Paul J.; Timmermans, Jean-Pierre; Adriaensen, Dirk

Pulmonary neuroepithelial bodies (NEBs) are densely innervated groups of neuroendocrine cells invariably accompanied by Clara-like cells. Together with NEBs, Clara-like cells form the so-called "NEB microenvironment," which recently has been assigned a potential pulmonary stem cell niche. Conclusive

Exfoliation syndrome: assembling the puzzle pieces.

Science.gov (United States)

Pasquale, Louis R; Borrás, Terete; Fingert, John H; Wiggs, Janey L; Ritch, Robert

2016-09-01

To summarize various topics and the cutting edge approaches to refine XFS pathogenesis that were discussed at the 21st annual Glaucoma Foundation Think Tank meeting in New York City, Sept. 19-20, 2014. The highlights of three categories of talks on cutting edge research in the field were summarized. Exfoliation syndrome (XFS) is a systemic disorder with a substantial ocular burden, including high rates of cataract, cataract surgery complications, glaucoma and retinal vein occlusion. New information about XFS is akin to puzzle pieces that do not quite join together to reveal a clear picture regarding how exfoliation material (XFM) forms. Meeting participants concluded that it is unclear how the mild homocysteinemia seen in XFS might contribute to the disarrayed extracellular aggregates characteristic of this syndrome. Lysyl oxidase-like 1 (LOXL1) variants are unequivocally genetic risk factors for XFS but exactly how these variants contribute to the assembly of exfoliation material (XFM) remains unclear. Variants in a new genomic region, CACNA1A associated with XFS, may alter calcium concentrations at the cell surface and facilitate XFM formation but much more work is needed before we can place this new finding in proper context. It is hoped that various animal model and ex vivo systems will emerge that will allow for proper assembly of the puzzle pieces into a coherent picture of XFS pathogenesis. A clear understanding of XFS pathogenesis may lead to 'upstream solutions' to reduce the ocular morbidity produced by XFS. © 2015 Acta Ophthalmologica Scandinavica Foundation. Published by John Wiley & Sons Ltd.

Phenotypic and Proteomic Characteristics of Human Dental Pulp Derived Mesenchymal Stem Cells from a Natal, an Exfoliated Deciduous, and an Impacted Third Molar Tooth

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Gurler Akpinar

2014-01-01

Full Text Available The level of heterogeneity among the isolated stem cells makes them less valuable for clinical use. The purpose of this study was to understand the level of heterogeneity among human dental pulp derived mesenchymal stem cells by using basic cell biology and proteomic approaches. The cells were isolated from a natal (NDPSCs, an exfoliated deciduous (stem cells from human exfoliated deciduous (SHED, and an impacted third molar (DPSCs tooth of three different donors. All three stem cells displayed similar features related to morphology, proliferation rates, expression of various cell surface markers, and differentiation potentials into adipocytes, osteocytes, and chondrocytes. Furthermore, using 2DE approach coupled with MALDI-TOF/TOF, we have generated a common 2DE profile for all three stem cells. We found that 62.3±7% of the protein spots were conserved among the three mesenchymal stem cell lines. Sixty-one of these conserved spots were identified by MALDI-TOF/TOF analysis. Classification of the identified proteins based on biological function revealed that structurally important proteins and proteins that are involved in protein folding machinery are predominantly expressed by all three stem cell lines. Some of these proteins may hold importance in understanding specific properties of human dental pulp derived mesenchymal stem cells.

Phototherapy up-regulates dentin matrix proteins expression and synthesis by stem cells from human-exfoliated deciduous teeth.

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Turrioni, Ana Paula S; Basso, Fernanda G; Montoro, Liege A; Almeida, Leopoldina de Fátima D de; Costa, Carlos A de Souza; Hebling, Josimeri

2014-10-01

The aim of this study was to evaluate the effects of infrared LED (850nm) irradiation on dentin matrix proteins expression and synthesis by cultured stem cells from human exfoliated deciduous teeth (SHED). Near-exfoliation primary teeth were extracted (n=3), and SHED cultures were characterized by immunofluorescence using STRO-1, CD44, CD146, Nanog and OCT3/4 antibodies, before experimental protocol. The SHEDs were seeded (3×10(4) cells/cm(2)) with DMEM containing 10% FBS. After 24-h incubation, the culture medium was replaced by osteogenic differentiation medium, and the cells were irradiated with LED light at energy densities (EDs) of 0 (control), 2, or 4J/cm(2) (n=8). The irradiated SHEDs were then evaluated for alkaline phosphatase (ALP) activity, total protein (TP) production, and collagen synthesis (SIRCOL™ Assay), as well as ALP, collagen type I (Col I), dentin sialophosphoprotein (DSPP), and dentin matrix acidic phosphoprotein (DMP-1) gene expression (qPCR). Data were analyzed by Kruskal-Wallis and Mann-Whitney tests (α=0.05). Increased ALP activity and collagen synthesis, as well as gene expression of DSPP and ALP, were observed for both EDs compared with non-irradiated cells. The ED of 4J/cm(2) also increased gene expression of COL I and DMP-1. In conclusion, infrared LED irradiation was capable of biostimulating SHEDs by increasing the expression and synthesis of proteins related with mineralized tissue formation, with overall better results for the energy dose of 4J/cm(2). Phototherapy is an additional approach for the clinical application of LED in Restorative Dentistry. Infrared LED irradiation of the cavity's floor could biostimulate subjacent pulp cells, improving local tissue healing. Copyright © 2014 Elsevier Ltd. All rights reserved.

Characterization of proximal pulmonary arterial cells from chronic thromboembolic pulmonary hypertension patients

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Quarck Rozenn

2012-03-01

Full Text Available Abstract Background Chronic thromboembolic pulmonary hypertension (CTEPH is associated with proximal pulmonary artery obstruction and vascular remodeling. We hypothesized that pulmonary arterial smooth muscle (PASMC and endothelial cells (PAEC may actively contribute to remodeling of the proximal pulmonary vascular wall in CTEPH. Our present objective was to characterize PASMC and PAEC from large arteries of CTEPH patients and investigate their potential involvement in vascular remodeling. Methods Primary cultures of proximal PAEC and PASMC from patients with CTEPH, with non-thromboembolic pulmonary hypertension (PH and lung donors have been established. PAEC and PASMC have been characterized by immunofluorescence using specific markers. Expression of smooth muscle specific markers within the pulmonary vascular wall has been studied by immunofluorescence and Western blotting. Mitogenic activity and migratory capacity of PASMC and PAEC have been investigated in vitro. Results PAEC express CD31 on their surface, von Willebrand factor in Weibel-Palade bodies and take up acetylated LDL. PASMC express various differentiation markers including α-smooth muscle actin (α-SMA, desmin and smooth muscle myosin heavy chain (SMMHC. In vascular tissue from CTEPH and non-thromboembolic PH patients, expression of α-SMA and desmin is down-regulated compared to lung donors; desmin expression is also down-regulated in vascular tissue from CTEPH compared to non-thromboembolic PH patients. A low proportion of α-SMA positive cells express desmin and SMMHC in the neointima of proximal pulmonary arteries from CTEPH patients. Serum-induced mitogenic activity of PAEC and PASMC, as well as migratory capacity of PASMC, were increased in CTEPH only. Conclusions Modified proliferative and/or migratory responses of PASMC and PAEC in vitro, associated to a proliferative phenotype of PASMC suggest that PASMC and PAEC could contribute to proximal vascular remodeling in CTEPH.

Ultrasound exfoliation of inorganic analogues of graphene.

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Stengl, Václav; Henych, Jiří; Slušná, Michaela; Ecorchard, Petra

2014-04-05

High-intensity ultrasound exfoliation of a bulk-layered material is an attractive route for large-scale preparation of monolayers. The monolayer slices could potentially be prepared with a high yield (up to 100%) in a few minutes. Exfoliation of natural minerals (such as tungstenite and molybdenite) or bulk synthetic materials (including hexagonal boron nitride (h-BN), hexagonal boron carbon nitride (h-BCN), and graphitic carbon nitride (g-C3N4)) in liquids leads to the breakdown of the 3D graphitic structure into a 2D structure; the efficiency of this process is highly dependent upon the physical effects of the ultrasound. Atomic force microscopy (AFM), transmission electron microscopy (TEM), and selected area electron diffraction (SAED) were employed to verify the quality of the exfoliation. Herein, this new method of exfoliation with ultrasound assistance for application to mono- and bilayered materials in hydrophobic and hydrophilic environments is presented.

Exfoliation of two-dimensional zeolites in liquid polybutadienes

KAUST Repository

Sabnis, Sanket; Tanna, Vijesh A.; Li, Chao; Zhu, Jiaxin; Vattipalli, Vivek; Nonnenmann, Stephen S.; Sheng, Guan; Lai, Zhiping; Winter, H. Henning; Fan, Wei

2017-01-01

Layered zeolite precursors were successfully exfoliated by brief shearing or sonication with the assistance of commercially available telechelic liquid polybutadienes at room temperature. The exfoliated zeolite nanosheets can form a stable

Liquid phase exfoliated graphene for electronic applications

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Sukumaran, Sheena S.; Jinesh, K. B.; Gopchandran, K. G.

2017-09-01

Graphene dispersions were prepared using the liquid phase exfoliation method with three different surfactants. One surfactant was used from each of the surfactant types, anionic, cationic, and non-ionic; those used, were sodium dodecylbenzene sulfonate (SDBS), cetyltrimethylammonium bromide (CTAB) and polyvinylpyrrolidone (PVP), respectively. Raman spectroscopy was used to investigate the number of layers and the nature of any defects present in the exfoliated graphene. The yield of graphene was found to be less with the non-ionic surfactant, PVP. The deconvolution of 2D peaks at ~2700 cm-1 indicated that graphene prepared using these surfactants resulted in sheets consisting of few-layer graphene. The ratio of intensity of the D and G bands in the Raman spectra showed that edge defect density is high for samples prepared with SDBS compared to the other two, and is attributed to the smaller size of the graphene sheets, as shown in the electron micrographs. In the case of the dispersion in PVP, it is found that the sizes of the graphene sheets are highly sensitive to the concentration of the surfactant used. Here, we have made an attempt to investigate the local density of states in the graphene sheets by measuring the tunnelling current-voltage characteristics. Graphene layers have shown consistent p-type behaviour when exfoliated with SDBS and n-type behaviour when exfoliated with CTAB, with a larger band gap for graphene exfoliated using CTAB. Hence, in addition to the known advantages of liquid phase exfoliation, we found that by selecting suitable surfactants, to a certain extent it is possible to tune the band gap and determine the type of majority carriers.

Exfoliated epithelial cells: potentials to explore gastrointestinal maturation of preterm infants Células epiteliais exfoliadas: potencial para investigar a maturação gastrointestinal em crianças pré-termo

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Bertrand Kaeffer

2010-03-01

Full Text Available Exfoliated epithelial cells represent valuable source of information on the physiopathological state of the mucosa. However, the interpretation of data obtained from exfoliated cells is complicated by the conditions of isolation as well as the health of the subject. Exfoliation is either: a a natural loss of body cells implying a molecular signal related to the turnover of terminally differentiated cells and to the progressive mobilization of proliferative as well as stem cells or b the result of manual exfoliation by applying mechanical constraints like scraping. Depending on the methodology of isolation, exfoliated epithelial cells are believed to be either in apoptosis or in anoïkis. Most studies are using microscopic examination to demonstrate the presence of typical cells along with measurements on a limited number of biomarkers. Only few studies using proteomics or transcriptomics are available and they open discussion about tissue references and normalization. The main advantage of measures realized on exfoliated epithelial cells is that they are strictly non-invasive and open the possibility to evaluate maturation of gastric and intestinal tissues in long-term experiments performed on the same animal or in translational research on samples recovered from preterm infants.Células epiteliais exfoliadas são uma fonte de informação valiosa sobre o estado fisiológico da mucosa. Contudo, a interpretação dos dados obtidos de células exfoliadas é complicado pelas condições de isolamento e da saúde do sujeito. A exfoliação é: a uma perda natural de células implicando um sinal molecular relacionado ao turnover terminal de células diferenciadas e à progressiva mobilização de células proliferativas e de células tronco ou b o resultado de aplicação de fatores mecânicos como raspagem. Dependendo do método de islolamento, acredita-se que podem estar em apoptose ou em anoikis. A maior parte dos estudos tem utilizado exame

Prevalence of pulmonary hypertension in sickle cell anaemia ...

African Journals Online (AJOL)

... subjected to echocardiography and pulmonary hypertension was deduced from their cardiac tricuspid regurgitant jet velocity. Other parameters measured were age, body mass index, full blood count, red cell indices, foetal haemoglobin, chest X-ray, liver function tests, lactate dehydrogenase and pulmonary function tests.

Mast Cell Inhibition Improves Pulmonary Vascular Remodeling in Pulmonary Hypertension

NARCIS (Netherlands)

Bartelds, Beatrijs; van Loon, Rosa Laura E.; Mohaupt, Saffloer; Wijnberg, Hans; Dickinson, Michael G.; Takens, Janny; van Albada, Mirjam; Berger, Rolf M. F.; Boersma, B.

Background: Pulmonary arterial hypertension (PAH) is a progressive angioproliferative disease with high morbidity and mortality. Although the histopathology is well described, its pathogenesis is largely unknown. We previously identified the increased presence of mast cells and their markers in a

Applications of the oral scraped (exfoliative) cytology in oral cancer and precancer.

Science.gov (United States)

Acha, Amelia; Ruesga, María T; Rodríguez, María J; Martínez de Pancorbo, María A; Aguirre, José M

2005-01-01

Scraped (exfoliative) cytology is a simple and harmless procedure, which has been a controversial technique according to its real validity in oral pathology. Lately it has re-emerged due to its application in oral precancer and cancer as a diagnostic and predictive method as well as for monitoring patients. New diagnostic techniques have been developed, such as "brush biopsy" and multiple molecular studies using the cells collected. In this review we are going to analyse the more novel aspects related with the applications of the scraped or exfoliative cytology in oral precancerous and cancerous pathology, specially focusing on molecular studies and their diagnostic and prognostic implications.

Osteogenic differentiation and mineralization of human exfoliated deciduous teeth stem cells on modified chitosan scaffold

Energy Technology Data Exchange (ETDEWEB)

Su, Wen-Ta, E-mail: f10549@ntut.edu.tw [Department of Chemical Engineering and Biotechnology, National Taipei University of Technology, Taipei, Taiwan (China); Wu, Pai-Shuen [Department of Chemical Engineering and Biotechnology, National Taipei University of Technology, Taipei, Taiwan (China); Ko, Chih-Sheng [PhytoHealth Corporation, Maywufa Biopharma Group, Taipei, Taiwan (China); Huang, Te-Yang [Mackay Memorial Hospital, Taipei, Taiwan (China)

2014-08-01

Stem cells from human exfoliated deciduous teeth (SHEDs) have been considered as alternative sources of adult stem cells in tissue engineering because of their potential to differentiate into multiple cell lineages. Strontium has an important function in bone remodeling because it can simulate bone formation and decrease bone resorption. In this study, the effects of strontium phosphate on the osteogenic differentiation of SHEDs were investigated. Strontium phosphate was found to enhance the osteogenic differentiation of SHEDs with up-regulated osteoblast-related gene expression. The proliferation of SHEDs was slightly inhibited by chitosan scaffolds; however, type-I collagen expression, alkaline phosphatase activity, and calcium deposition on chitosan scaffolds containing strontium were significantly enhanced. Furthermore, cells seeded in a 3D scaffold under dynamic culture at an optimal fluid rate might enhance cellular differentiation than static culture in osteoblastic gene expression. This experiment might provide a useful cell resource and dynamic 3D culture for tissue engineering and bone repair. - Highlights: • SHEDs have been considered as alternative sources of adult stem cells in tissue engineering • Strontium phosphate can enhance the osteogenic differentiation of SHEDs • 3D scaffold under dynamic culture with optimal fluid rate enhance cellular differentiation.

Osteogenic differentiation and mineralization of human exfoliated deciduous teeth stem cells on modified chitosan scaffold

International Nuclear Information System (INIS)

Su, Wen-Ta; Wu, Pai-Shuen; Ko, Chih-Sheng; Huang, Te-Yang

2014-01-01

Stem cells from human exfoliated deciduous teeth (SHEDs) have been considered as alternative sources of adult stem cells in tissue engineering because of their potential to differentiate into multiple cell lineages. Strontium has an important function in bone remodeling because it can simulate bone formation and decrease bone resorption. In this study, the effects of strontium phosphate on the osteogenic differentiation of SHEDs were investigated. Strontium phosphate was found to enhance the osteogenic differentiation of SHEDs with up-regulated osteoblast-related gene expression. The proliferation of SHEDs was slightly inhibited by chitosan scaffolds; however, type-I collagen expression, alkaline phosphatase activity, and calcium deposition on chitosan scaffolds containing strontium were significantly enhanced. Furthermore, cells seeded in a 3D scaffold under dynamic culture at an optimal fluid rate might enhance cellular differentiation than static culture in osteoblastic gene expression. This experiment might provide a useful cell resource and dynamic 3D culture for tissue engineering and bone repair. - Highlights: • SHEDs have been considered as alternative sources of adult stem cells in tissue engineering • Strontium phosphate can enhance the osteogenic differentiation of SHEDs • 3D scaffold under dynamic culture with optimal fluid rate enhance cellular differentiation

Clay exfoliation and polymer/clay aerogels by supercritical carbon dioxide

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Simona eLongo

2013-11-01

Full Text Available Supercritical carbon dioxide (scCO2 treatments of a montmorillonite (MMT intercalated with ammonium cations bearing two long hydrocarbon tails (organo-modified MMT, OMMT led to OMMT exfoliation, with loss of the long-range order in the packing of the hydrocarbon tails and maintenance of the long-range order in the clay layers. The intercalated and the derived exfoliated OMMT have been deeply characterized, mainly by X-ray diffraction analyses. Monolithic composite aerogels, with large amounts of both intercalated and exfoliated OMMT and including the nanoporous-crystalline δ form of syndiotactic polystyrene (s-PS, have been prepared, by scCO2 extractions of s-PS-based gels. Also for high OMMT content, the gel and aerogel preparation procedures occur without re-aggregation of the exfoliated clay, which is instead observed for other kinds of polymer processing. Aerogels with the exfoliated OMMT have more even dispersion of the clay layers, higher elastic modulus and larger surface area than aerogels with the intercalated OMMT. Extremely light materials with relevant transport properties could be prepared. Moreover, s-PS-based aerogels with exfoliated OMMT could be helpful for the handling of exfoliated clay minerals.

Mechanical behaviour of cyclic olefin copolymer/exfoliated graphite nanoplatelets nanocomposites foamed through supercritical carbon dioxide

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A. Biani

2016-12-01

Full Text Available A cycloolefin copolymer matrix was melt mixed with exfoliated graphite nanoplatelets (xGnP and the resulting nanocomposites were foamed by supercritical carbon dioxide. The density of the obtained foams decreased with the foaming pressure. Moreover, xGnP limited the cell growth during the expansion process thus reducing the cell diameter (from 1.08 to 0.22 mm with an XGnP amount of 10 wt% at 150 bar and increasing the cell density (from 12 to 45 cells/mm2 with a nanofiller content of 10 wt% at 150 bar. Electron microscopy observations of foams evidenced exfoliation and orientation of the nanoplatelets along the cell walls. Quasi-static compressive tests and tensile creep tests on foams clearly indicated that xGnP improved the modulus (up to a factor of 10 for a xGnP content of 10 wt% and the creep stability.

Preparation and characterization of exfoliated polyaniline/montmorillonite nanocomposites

International Nuclear Information System (INIS)

Narayanan, Binitha N.; Koodathil, Ranjana; Gangadharan, Tripti; Yaakob, Zahira; Saidu, Femina K.; Chandralayam, Soumini

2010-01-01

Transition metal ions were exchanged with the interlamellar cations of montmorillonite clays and polymerization of aniline was done within the layers. The delaminated clay layers upon ion exchange resulted in exfoliated polyaniline/clay nanocomposite formation which has profound effects on polymer structure, properties and electrical conduction mechanisms. Here we offer polyaniline (PANI)/montmorillonite exfoliated nanocomposite synthesized through a simple, cheap route which need not require complicated and less economical organophilic modification. The prepared composites were characterized using XRD, FTIR, and TG/DTA to prove exfoliation.

Preparation and characterization of exfoliated polyaniline/montmorillonite nanocomposites

Energy Technology Data Exchange (ETDEWEB)

Narayanan, Binitha N., E-mail: binithann@yahoo.co.i [Department of Chemistry, Sree Neelakanta Government Sanskrit College, Pattambi, Palakkad 679306, Kerala (India); Department of Chemical and Process Engineering, Faculty of Engineering, National University of Malaysia, 43600 UKM Bangi, Selangor (Malaysia); Koodathil, Ranjana; Gangadharan, Tripti [Department of Chemistry, Sree Neelakanta Government Sanskrit College, Pattambi, Palakkad 679306, Kerala (India); Yaakob, Zahira [Department of Chemical and Process Engineering, Faculty of Engineering, National University of Malaysia, 43600 UKM Bangi, Selangor (Malaysia); Saidu, Femina K.; Chandralayam, Soumini [Department of Chemistry, Sree Neelakanta Government Sanskrit College, Pattambi, Palakkad 679306, Kerala (India)

2010-04-15

Transition metal ions were exchanged with the interlamellar cations of montmorillonite clays and polymerization of aniline was done within the layers. The delaminated clay layers upon ion exchange resulted in exfoliated polyaniline/clay nanocomposite formation which has profound effects on polymer structure, properties and electrical conduction mechanisms. Here we offer polyaniline (PANI)/montmorillonite exfoliated nanocomposite synthesized through a simple, cheap route which need not require complicated and less economical organophilic modification. The prepared composites were characterized using XRD, FTIR, and TG/DTA to prove exfoliation.

Cell therapy with bone marrow mononuclear cells in elastase-induced pulmonary emphysema.

Science.gov (United States)

Longhini-Dos-Santos, Nathalia; Barbosa-de-Oliveira, Valter Abraão; Kozma, Rodrigo Heras; Faria, Carolina Arruda de; Stessuk, Talita; Frei, Fernando; Ribeiro-Paes, João Tadeu

2013-04-01

Emphysema is characterized by destruction of alveolar walls with loss of gas exchange surface and consequent progressive dyspnea. This study aimed to evaluate the efficiency of cell therapy with bone marrow mononuclear cells (BMMC) in an animal model of elastase-induced pulmonary emphysema. Emphysema was induced in C57Bl/J6 female mice by intranasal instillation of elastase. After 21 days, the mice received bone marrow mononuclear cells from EGFP male mice with C57Bl/J6 background. The groups were assessed by comparison and statistically significant differences (p pulmonary emphysema.

Adhesive tape exfoliation: Why it works for graphene

Science.gov (United States)

Bohr, Jakob

2015-03-01

Single-crystal graphite can be cleaved by the use of an adhesive tape. This was also the initial route for obtaining graphene, a one-layer thick graphite slab. In this letter a few simple and fun considerations are presented in an attempt to shed some light on why this procedure is successful. In particular on the nature of the surprisingly small number of repetitive steps that are needed in order to obtain a single-layer slab. Two frameworks for exfoliation are investigated: parallel exfoliation involving repetitive simultaneous cleaving, the other, serial exfoliation, which involves the repetitive cleaving of a single chunk of graphite. For both cases, parallel and serial exfoliation, it is investigated how many generations of cleavages are needed. An approximate model with the probability distribution expressed as a simple closed form is presented and compared with the simulations.

Danshensu prevents hypoxic pulmonary hypertension in rats by inhibiting the proliferation of pulmonary artery smooth muscle cells via TGF-β-smad3-associated pathway.

Science.gov (United States)

Zhang, Ning; Dong, Mingqing; Luo, Ying; Zhao, Feng; Li, Yongjun

2018-02-05

Hypoxic pulmonary hypertension is characterized by the remodeling of pulmonary artery. Previously we showed that tanshinone IIA, one lipid-soluble component from the Chinese herb Danshen, ameliorated hypoxic pulmonary hypertension by inhibiting pulmonary artery remodeling. Here we explored the effects of danshensu, one water-soluble component of Danshen, on hypoxic pulmonary hypertension and its mechanism. Rats were exposed to hypobaric hypoxia for 4 weeks to develop hypoxic pulmonary hypertension along with administration of danshensu. Hemodynamics and pulmonary arterial remodeling index were measured. The effects of danshensu on the proliferation of primary pulmonary artery smooth muscle cells and transforming growth factor-β-smad3 pathway were assessed in vitro. Danshensu significantly decreased the right ventricle systolic pressure, the right ventricle hypertrophy and pulmonary vascular remodeling index in hypoxic pulmonary hypertension rats. Danshensu also reduced the increased expression of transforming growth factor-β and phosphorylation of smad3 in pulmonary arteries in hypoxic pulmonary hypertension rats. In vitro, danshensu inhibited the hypoxia- or transforming growth factor-β-induced proliferation of primary pulmonary artery smooth muscle cells. Moreover, danshensu decreased the hypoxia-induced expression and secretion of transforming growth factor in primary pulmonary adventitial fibroblasts and NR8383 cell line, inhibited the hypoxia or transforming growth factor-β-induced phosphorylation of smad3 in rat primary pulmonary artery smooth muscle cells. These results demonstrate that danshensu ameliorates hypoxic pulmonary hypertension in rats by inhibiting the hypoxia-induced proliferation of pulmonary artery smooth muscle cells, and the inhibition effects is associated with transforming growth factor-β-smad3 pathway. Therefore danshensu may be a potential treatment for hypoxic pulmonary hypertension. Copyright © 2017 Elsevier B.V. All rights

Central role of T helper 17 cells in chronic hypoxia-induced pulmonary hypertension.

Science.gov (United States)

Maston, Levi D; Jones, David T; Giermakowska, Wieslawa; Howard, Tamara A; Cannon, Judy L; Wang, Wei; Wei, Yongyi; Xuan, Weimin; Resta, Thomas C; Gonzalez Bosc, Laura V

2017-05-01

Inflammation is a prominent pathological feature in pulmonary arterial hypertension, as demonstrated by pulmonary vascular infiltration of inflammatory cells, including T and B lymphocytes. However, the contribution of the adaptive immune system is not well characterized in pulmonary hypertension caused by chronic hypoxia. CD4 + T cells are required for initiating and maintaining inflammation, suggesting that these cells could play an important role in the pathogenesis of hypoxic pulmonary hypertension. Our objective was to test the hypothesis that CD4 + T cells, specifically the T helper 17 subset, contribute to chronic hypoxia-induced pulmonary hypertension. We compared indices of pulmonary hypertension resulting from chronic hypoxia (3 wk) in wild-type mice and recombination-activating gene 1 knockout mice (RAG1 -/- , lacking mature T and B cells). Separate sets of mice were adoptively transferred with CD4 + , CD8 + , or T helper 17 cells before normoxic or chronic hypoxic exposure to evaluate the involvement of specific T cell subsets. RAG1 -/- mice had diminished right ventricular systolic pressure and arterial remodeling compared with wild-type mice exposed to chronic hypoxia. Adoptive transfer of CD4 + but not CD8 + T cells restored the hypertensive phenotype in RAG1 -/- mice. Interestingly, RAG1 -/- mice receiving T helper 17 cells displayed evidence of pulmonary hypertension independent of chronic hypoxia. Supporting our hypothesis, depletion of CD4 + cells or treatment with SR1001, an inhibitor of T helper 17 cell development, prevented increased pressure and remodeling responses to chronic hypoxia. We conclude that T helper 17 cells play a key role in the development of chronic hypoxia-induced pulmonary hypertension. Copyright © 2017 the American Physiological Society.

Endothelial cell energy metabolism, proliferation, and apoptosis in pulmonary hypertension.

Science.gov (United States)

Xu, Weiling; Erzurum, Serpil C

2011-01-01

Pulmonary arterial hypertension (PAH) is a fatal disease characterized by impaired regulation of pulmonary hemodynamics and excessive growth and dysfunction of the endothelial cells that line the arteries in PAH lungs. Establishment of methods for culture of pulmonary artery endothelial cells from PAH lungs has provided the groundwork for mechanistic translational studies that confirm and extend findings from model systems and spontaneous pulmonary hypertension in animals. Endothelial cell hyperproliferation, survival, and alterations of biochemical-metabolic pathways are the unifying endothelial pathobiology of the disease. The hyperproliferative and apoptosis-resistant phenotype of PAH endothelial cells is dependent upon the activation of signal transducer and activator of transcription (STAT) 3, a fundamental regulator of cell survival and angiogenesis. Animal models of PAH, patients with PAH, and human PAH endothelial cells produce low nitric oxide (NO). In association with the low level of NO, endothelial cells have reduced mitochondrial numbers and cellular respiration, which is associated with more than a threefold increase in glycolysis for energy production. The shift to glycolysis is related to low levels of NO and likely to the pathologic expression of the prosurvival and proangiogenic signal transducer, hypoxia-inducible factor (HIF)-1, and the reduced mitochondrial antioxidant manganese superoxide dismutase (MnSOD). In this article, we review the phenotypic changes of the endothelium in PAH and the biochemical mechanisms accounting for the proliferative, glycolytic, and strongly proangiogenic phenotype of these dysfunctional cells, which consequently foster the panvascular progressive pulmonary remodeling in PAH. © 2011 American Physiological Society.

Separation medium containing thermally exfoliated graphite oxide

Science.gov (United States)

Prud'homme, Robert K. (Inventor); Aksay, Ilhan A. (Inventor); Herrera-Alonso, Margarita (Inventor)

2012-01-01

A separation medium, such as a chromatography filling or packing, containing a modified graphite oxide material, which is a thermally exfoliated graphite oxide with a surface area of from about 300 m.sup.2/g to 2600 m.sup.2/g, wherein the thermally exfoliated graphite oxide has a surface that has been at least partially functionalized.

Group B streptococcus exploits vaginal epithelial exfoliation for ascending infection.

Science.gov (United States)

Vornhagen, Jay; Armistead, Blair; Santana-Ufret, Verónica; Gendrin, Claire; Merillat, Sean; Coleman, Michelle; Quach, Phoenicia; Boldenow, Erica; Alishetti, Varchita; Leonhard-Melief, Christina; Ngo, Lisa Y; Whidbey, Christopher; Doran, Kelly S; Curtis, Chad; Waldorf, Kristina M Adams; Nance, Elizabeth; Rajagopal, Lakshmi

2018-04-09

Thirteen percent of pregnancies result in preterm birth or stillbirth, accounting for fifteen million preterm births and three and a half million deaths annually. A significant cause of these adverse pregnancy outcomes is in utero infection by vaginal microorganisms. To establish an in utero infection, vaginal microbes enter the uterus by ascending infection; however, the mechanisms by which this occurs are unknown. Using both in vitro and murine models of vaginal colonization and ascending infection, we demonstrate how a vaginal microbe, group B streptococcus (GBS), which is frequently associated with adverse pregnancy outcomes, uses vaginal exfoliation for ascending infection. GBS induces vaginal epithelial exfoliation by activation of integrin and β-catenin signaling. However, exfoliation did not diminish GBS vaginal colonization as reported for other vaginal microbes. Rather, vaginal exfoliation increased bacterial dissemination and ascending GBS infection, and abrogation of exfoliation reduced ascending infection and improved pregnancy outcomes. Thus, for some vaginal bacteria, exfoliation promotes ascending infection rather than preventing colonization. Our study provides insight into mechanisms of ascending infection by vaginal microbes.

Unicentric study of cell therapy in chronic obstructive pulmonary disease/pulmonary emphysema

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João Tadeu Ribeiro-Paes

2011-01-01

Full Text Available João Tadeu Ribeiro-Paes1, Aldemir Bilaqui2, Oswaldo T Greco2, Milton Artur Ruiz2, Monica Y Marcelino3, Talita Stessuk1, Carolina A de Faria3, Mario R Lago21Universidade Estadual Paulista (UNESP, Campus de Assis, Assis, SP, Brazil; 2Cardiovascular Diseases Institute (IMC, São José do Rio Preto, SP, Brazil; 3Inter-units Biotechnology Post Graduation Program, USP-IPT-I, Butantan, São Paulo, SP, BrazilAbstract: Within the chronic obstructive pulmonary disease (COPD spectrum, lung emphysema presents, as a primarily histopathologic feature, the destruction of pulmonary parenchyma and, accordingly, an increase in the airflow obstruction distal to the terminal bronchiole. Notwithstanding the significant advances in prevention and treatment of symptoms, no effective or curative therapy has been accomplished. In this context, cellular therapy with stem cells (SCs arises as a new therapeutic approach, with a wide application potential. The purpose of this study is to evaluate the safety of SCs infusion procedure in patients with advanced COPD (stage IV dyspnea. After selection, patients underwent clinical examination and received granulocyte colony-stimulating factor, immediately prior to the bone marrow harvest. The bone marrow mononuclear cells (BMMC were isolated and infused into a peripheral vein. The 12-month follow-up showed a significant improvement in the quality of life, as well as a clinical stable condition, which suggest a change in the natural process of the disease. Therefore, the proposed methodology in this study for BMMC cell therapy in sufferers of advanced COPD was demonstrated to be free of significant adverse effects. Although a larger sample and a greater follow-up period are needed, it is possible to infer that BMMC cell therapy introduces an unprecedented change in the course or in the natural history of emphysema, inhibiting or slowing the progression of disease. This clinical trial was registered with ClinicalTrials.gov (NCT

Exfoliative Cytology in the Oral Mucosa of Patients with Fanconi Anaemia: A Morphometric Approach

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Maria Angela Naval Machado

2017-04-01

Full Text Available Patients with Fanconi anaemia (FA are prone to develop squamous cell carcinomas at an early age. Exfoliative cytology can be used to detect changes to the health of the oral mucosa. Objective: The aim of this study was to evaluate morphometrical and morphological changes using exfoliative cytology and to analyse and quantify the proliferative activity using silver nucleolar organiser regions (AgNOR in epithelial cells of the tongue in FA patients,after haematopoietic stem cell transplantation (HSCT. Methods: Oral smears were collected from the tongues of 20 FA children and adolescents after haematopoietic stem cell transplantation (FA and 20 healthy children (C using exfoliative cytology. The smears were stained using the Papanicolaou technique and silver impregnation. The cells were morphologically analysed and the nuclear area (NA, the cytoplasmic area (CA, and the nucleusto-cytoplasm area ratio (NA/CA were calculated. Results: Mean values for the FA and C groups were: NA (71.85 and 55.21μm.; p< 0.01; CA (2127.48 and 1441.61μm.; p< 0.01; NA/CA (0.03 and 0.04; p< 0.01, respectively. A significant increase in the NA and CA for the FA group (p< 0.01 was seen, and an alteration in the NA/CA ratio. No morphological differences were found between the groups. Class I smears were predominant in both groups. No differences were found between the groups for the mean values of AgNORs per nucleus. Conclusion: This study suggests that morphological changes occurred in the oral epithelium cells of children and adolescents with Fanconi anaemia when subjected to HSCT.

Controlling the properties of graphene produced by electrochemical exfoliation

International Nuclear Information System (INIS)

Hofmann, Mario; D Nguyễn, Tuân; Chiang, Wan-Yu; Hsieh, Ya-Ping

2015-01-01

The synthesis of graphene with controllable electronic and mechanical characteristics is of significant importance for its application in various fields ranging from drug delivery to energy storage. Electrochemical exfoliation of graphite has yielded graphene with widely varying behavior and could be a suitable approach. Currently, however the limited understanding of the exfoliation process obstructs targeted modification of graphene properties. We here investigate the process of electrochemical exfoliation and the impact of its parameters on the produced graphene. Using in situ optical and electrical measurements we determine that solvent intercalation is the required first step and the degree of intercalation controls the thickness of the exfoliated graphene. Electrochemical decomposition of water into gas bubbles causes the expansion of graphite and controls the functionalization and lateral size of the exfoliated graphene. Both process steps proceed at different time scales and can be individually addressed through application of pulsed voltages. The potential of the presented approach was demonstrated by improving the performance of graphene-based transparent conductors by 30times. (paper)

The effect of stem cell from human exfoliated deciduous teeth on T lymphocyte proliferation.

Science.gov (United States)

Alipour, Razieh; Adib, Minoo; Hashemi-Beni, Batool; Sadeghi, Farzaneh

2014-01-01

Mesenchymal stem cells (MSC), a specific type of adult tissue stem cell; have the immunosuppressive effects that make them valuable targets for regenerative medicine and treatment of many human illnesses. Hence, MSC have been the subject of numerous studies. The classical source of MSC is adult bone marrow (BM). Due to many shortcomings of harvesting MSC from BM, finding the alternative sources for MSC is an urgent. Stem cells from human exfoliated deciduous teeth (SHED) are relative new MSC populations that fulfill these criteria but their potential immunosuppressive effect has not been studied enough yet. Thus, in this work the effect of SHED on the proliferation of in vitro activated T lymphocytes were explored. In this study, both mitogen and alloantigen activated T cells were cultured in the presence of different numbers of SHED. In some co-cultures, activated T cells were in direct contact to MSCs and in other co-cultures; they were separated from SHED by a permeable membrane. In all co-cultures, the proliferation of T cells was measured by ELISA Bromodeoxyuridine proliferation assay. In general, our results showed that SHED significantly suppress the proliferation of activated T cells in a dose-dependent manner. Moreover, the suppression was slightly stronger when MSCs were in physical contact to activated T cells. This study showed that SHED likewise other MSC populations can suppress the activation of T lymphocytes, which can be used instead of BM derived MSCs in many investigational and clinical applications.

Karakterisasi stem cell pulpa gigi sulung dengan modifikasi enzim tripsin (The characterization of stem cells from human exfoliated deciduous teeth using trypsin enzym

Directory of Open Access Journals (Sweden)

Tri Wijayanti Puspitasari

2014-06-01

Full Text Available Background: Now a days, treatment in dentistry, using tissue regeneration that based on the stem cells from human exfoliated deciduous teeth (SHED, grows rapidly. For several reason, the isolated and cultured SHED is difficult to be applied in Indonesia, therefore the modification is needed. This difficulties were caused by the pulp anatomy, the heterogeneous populations in the pulp chamber and the limitations of tools and materials at the laboratory. Purpose: This research was aimed to examine that the modifications of isolation and culture technique of SHEDs for characterization by using the marker of CD105. Methods: The research was experimental laboratory with the cross sectional design. The samples were the human exfoliated deciduous teeth from the children patients of Pediatric Dentistry Department of Universitas Airlangga Dental Hospital which matched the criteria. Dental pulps were isolated and cultured by using the modifications of Trypsin enzymes. Results: The healthy SHEDs could be produced from the modifications of isolation and culture and positively shown the expression of marker CD105 which were indicated by the fluorencent microscope. Conclusion: SHED which isolated and cultured by using the modified techniques, positively characterized by using marker CD105.Latar Belakang: Pengobatan kedokteran gigi berkembang dengan pesat terutama di bidang regenerasi jaringan berbasis Stem Cells from Human Exfoliated Deciduous Teeth (SHED. Di Indonesia, isolasi dan kultur SHED sulit sehingga perlu dilakukan modifikasi. Kendala ini muncul karena jaringan pulpa yang kecil, heterogen dan keterbatasan alat dan bahan di laboratorium. Tujuan: Penelitian ini bertujuan untuk meneliti modifikasi pada cara isolasi dan kultur SHED untuk karakterisasi menggunakan maker CD105. Metode: Jenis penelitian ini adalah eksperimental laboratoris dengan rancangan cross sectional. Sampel penelitian adalah gigi sulung dari pasien anak di Klinik Kedokteran Gigi Anak

A Rare Case of Diffuse Idiopathic Pulmonary Neuroendocrine Cell Hyperplasia

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Godwin Ofikwu

2015-01-01

Full Text Available Diffuse idiopathic pulmonary neuroendocrine cell hyperplasia (DIPNECH is a rare clinical condition with only about 100 cases reported in the literature. It is characterized by primary hyperplasia of pulmonary neuroendocrine cells (PNECs which are specialized epithelial cells located throughout the entire respiratory tract, from the trachea to the terminal airways. DIPNECH appears in various forms that include diffuse proliferation of scattered neuroendocrine cells, small nodules, or a linear proliferation. It is usually seen in middle-aged, nonsmoking women with symptoms of cough, dyspnea, and wheezing. We present a 45-year-old, nonsmoking woman who presented with symptoms of DIPNECH associated with bilateral pulmonary nodules and left hilar adenopathy. Of interest, DIPNECH in our patient was associated with metastatic pulmonary carcinoids, papillary carcinoma of the left breast, oncocytoma and angiomyolipoma of her left kidney, and cortical nodules suggestive of tuberous sclerosis. She had video assisted thoracoscopic surgery (VATS, modified radical mastectomy with reconstruction, and radical nephrectomy. She is currently symptom-free most of the time with over two years of follow-up.

Exfoliation of two-dimensional zeolites in liquid polybutadienes

KAUST Repository

Sabnis, Sanket

2017-06-16

Layered zeolite precursors were successfully exfoliated by brief shearing or sonication with the assistance of commercially available telechelic liquid polybutadienes at room temperature. The exfoliated zeolite nanosheets can form a stable suspension in an organic solvent, providing exciting potential for the fabrication of zeolite membranes, composite materials and hierarchical zeolites.

Effect of photobiomodulation on viability and proliferation of stem cells from exfoliated deciduous teeth under different nutritional conditions

Science.gov (United States)

Morato de Souza, Letícia; Guilherme Roque Rinco, Ugo; Aparecida Tavares Aguiar, Daniela; Aparecido de Almeida Junior, Luciano; Cosme-Silva, Leopoldo; Marchini Oliveira, Thais; Teixeira Marques, Nádia Carolina; Thiemy Sakai, Vivien

2018-02-01

This study aimed to evaluate the effect of different doses of low-level laser irradiation on the viability and proliferation of stem cells from exfoliated deciduous teeth (SHED) cultured under nutritional deficit (cellular stress) or regular nutritional conditions. SHED underwent irradiation by a red laser between 1.2 and 6.2 J cm-2. Prior to the irradiation, all groups received culture medium (MEMα, Eagle’s minimum essential medium alpha modification) supplemented with 1% of fetal bovine serum (FBS) for 1 h. After the irradiation, cells received MEMα supplemented with 10% of FBS (regular nutrition) or 1% of FBS (nutritional deficit). Cell viability and proliferation were respectively determined by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) and crystal violet assays 6 and 24 h after irradiation (P  cell viability and proliferation of SHED after laser irradiation, except for 1.2 J cm-2.

Pulmonary stromal cells induce the generation of regulatory DC attenuating T-cell-mediated lung inflammation.

Science.gov (United States)

Li, Qian; Guo, Zhenhong; Xu, Xiongfei; Xia, Sheng; Cao, Xuetao

2008-10-01

The tissue microenvironment may affect the development and function of immune cells such as DC. Whether and how the pulmonary stromal microenvironment can affect the development and function of lung DC need to be investigated. Regulatory DC (DCreg) can regulate T-cell response. We wondered whether such regulatory DC exist in the lung and what is the effect of the pulmonary stromal microenvironment on the generation of DCreg. Here we demonstrate that murine pulmonary stromal cells can drive immature DC, which are regarded as being widely distributed in the lung, to proliferate and differentiate into a distinct subset of DCreg, which express high levels of CD11b but low levels of MHC class II (I-A), CD11c, secrete high amounts of IL-10, NO and prostaglandin E2 (PGE2) and suppress T-cell proliferation. The natural counterpart of DCreg in the lung with similar phenotype and regulatory function has been identified. Pulmonary stroma-derived TGF-beta is responsible for the differentiation of immature DC to DCreg, and DCreg-derived PGE2 contributes to their suppression of T-cell proliferation. Moreover, DCreg can induce the generation of CD4+CD25+Foxp3+ Treg. Importantly, infusion with DCreg attenuates T-cell-mediated eosinophilic airway inflammation in vivo. Therefore, the pulmonary microenvironment may drive the generation of DCreg, thus contributing to the maintenance of immune homoeostasis and the control of inflammation in the lung.

Anion-exchange membranes derived from quaternized polysulfone and exfoliated layered double hydroxide for fuel cells

Energy Technology Data Exchange (ETDEWEB)

Liu, Wan; Liang, Na; Peng, Pai; Qu, Rong; Chen, Dongzhi; Zhang, Hongwei, E-mail: hanqiujiang@163.com

2017-02-15

Layered double hydroxides (LDH) are prepared by controlling urea assisted homogeneous precipitation conditions. Morphology and crystallinity of LDHs are confirmed by X-ray diffraction and scanning electron microscope. After LDHs are incorporated into quaternized polysulfone membranes, transmission electron microscope is used to observe the exfoliated morphology of LDH sheets in the membranes. The properties of the nanocomposite membranes, including water uptake, swelling ratio, mechanical property and ionic conductivity are investigated. The nanocomposite membrane containing 5% LDH sheets shows more balanced performances, exhibiting an ionic conductivity of 2.36×10{sup −2} S cm{sup −1} at 60 °C. - Graphical abstract: Anion-exchange membrane based on quaternized polysulfone and exfoliated layered double hydroxide is optically transparent and has good ionic properties.

Effect of prepro-calcitonin gene-related peptide-expressing endothelial progenitor cells on pulmonary hypertension.

Science.gov (United States)

Zhao, Qiang; Liu, Zixiong; Wang, Zhe; Yang, Cheng; Liu, Jun; Lu, Jun

2007-08-01

Calcitonin gene-related peptide (CGRP) is a potent smooth muscle cell proliferation inhibitor and vasodilator. It is now believed that CGRP plays an important role in maintaining a low pulmonary vascular resistance. We evaluated the therapeutic effect of intravenously administered CGRP-expressing endothelial progenitor cells (EPCs) on left-to-right shunt-induced pulmonary hypertension in rats. Endothelial progenitor cells were obtained from cultured human peripheral blood mononuclear cells. The genetic sequence for CGRP was subcloned into cultured EPCs by human expression plasmid. Pulmonary hypertension was established in immunodeficient rats with an abdominal aorta to inferior vena cava shunt operation. The transfected EPCs were injected through the left jugular vein at 10 weeks after the shunt operation. Mean pulmonary artery pressure and total pulmonary vascular resistance were detected with right cardiac catheterization at 4 weeks. The distribution of EPCs in the lung tissue was examined with immunofluorescence technique. Histopathologic changes in the structure of the pulmonary arteries was observed with electron microscopy and subjected to computerized image analysis. The lungs of rats transplanted with CGRP-expressing EPCs demonstrated a decrease in both mean pulmonary artery pressure (17.64 +/- 0.79 versus 22.08 +/- 0.95 mm Hg; p = 0.018) and total pulmonary vascular resistance (1.26 +/- 0.07 versus 2.45 +/- 0.18 mm Hg x min/mL; p = 0.037) at 4 weeks. Immunofluorescence revealed that intravenously administered cells were incorporated into the pulmonary vasculature. Pulmonary vascular remodeling was remarkably attenuated with the administration of CGRP-expressing EPCs. The transplantation of CGRP-expressing EPCs may effectively attenuate established pulmonary hypertension and exert reversal effects on pulmonary vascular remodeling. Our findings suggest that the therapy based on the combination of both CGRP transfection and EPCs may be a potentially useful

The mechanisms of surface exfoliation in H and He implanted Si crystals

International Nuclear Information System (INIS)

Reboh, S.; Mattos, A.A.D. de; Schaurich, F.; Fichtner, P.F.P.; Beaufort, M.F.; Barbot, J.F.

2011-01-01

We report on the exfoliation mechanisms in light gas implanted Si. Microstructure characterization, extensive statistical analysis and solid mechanics theory show that exfoliation is caused by microcracks growing close to equilibrium pressure for high fluences. For lower fluences, cracks evolve at under-equilibrium pressure and exfoliation relies on a coalescence mechanism assisted by cleavage. This provides long-range, collective and efficient stress relief for clusters of cracks, causing enhancement of the exfoliation. The physical processes are independent of the irradiation energy.

Management of exfoliative glaucoma: challenges and solutions.

Science.gov (United States)

Holló, Gábor; Katsanos, Andreas; Konstas, Anastasios Gp

2015-01-01

Exfoliative glaucoma is the most common type of secondary open-angle glaucoma worldwide. It is characterized by high intraocular pressure (IOP) and worse 24-hour IOP characteristics. In order to minimize progression, treatment of exfoliative glaucoma has to provide a low long-term mean IOP and good 24-hour IOP control. To achieve these goals, fixed-dose combination eye drops, argon and selective laser trabeculoplasty, and various forms of surgery (trabeculectomy, deep sclerectomy, viscocanalostomy, ab interno trabeculotomy, trabecular aspiration, and cataract surgery) all need to be considered during the long-term management of the disease. Since exfoliative glaucoma is a disease of the elderly, and is frequently associated with systemic vascular disease, interdisciplinary consultations are of great clinical importance. These management aspects and the current medical, laser, and surgical results are covered in this review, with a special focus on the needs of the general ophthalmologist.

Rare Case of Duodenal Metastasis From Pulmonary Squamous Cell Carcinoma

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Zain Memon DO

2017-10-01

Full Text Available Pulmonary squamous cell carcinoma is the second most common non–small cell malignancy of the lung. It commonly metastasizes to the adrenal glands, bone, liver, brain, and kidneys. Most occurrences of metastatic squamous cell carcinoma involving the gastrointestinal tract originate from primary lung tumors. Metastasis to the duodenum, however, is exceedingly rare, with very few cases of stomach or duodenal involvement described in the literature. We report the case of a patient with stage IV pulmonary squamous cell carcinoma metastasizing to the duodenum with an uncommon presentation to add to the paucity of literature available regarding this rare finding.

Antioxidant mechanism of Rutin on hypoxia-induced pulmonary arterial cell proliferation.

Science.gov (United States)

Li, Qian; Qiu, Yanli; Mao, Min; Lv, Jinying; Zhang, Lixin; Li, Shuzhen; Li, Xia; Zheng, Xiaodong

2014-11-18

Reactive oxygen species (ROS) are involved in the pathologic process of pulmonary arterial hypertension as either mediators or inducers. Rutin is a type of flavonoid which exhibits significant scavenging properties on oxygen radicals both in vitro and in vivo. In this study, we proposed that rutin attenuated hypoxia-induced pulmonary artery smooth muscle cell (PASMC) proliferation by scavenging ROS. Immunofluorescence data showed that rutin decreased the production of ROS, which was mainly generated through mitochondria and NADPH oxidase 4 (Nox4) in pulmonary artery endothelial cells (PAECs). Western blot results provided further evidence on rutin increasing expression of Nox4 and hypoxia-inducible factor-1α (HIF-1α). Moreover, cell cycle analysis by flow cytometry indicated that proliferation of PASMCs triggered by hypoxia was also repressed by rutin. However, N-acetyl-L-cysteine (NAC), a scavenger of ROS, abolished or diminished the capability of rutin in repressing hypoxia-induced cell proliferation. These data suggest that rutin shows a potential benefit against the development of hypoxic pulmonary arterial hypertension by inhibiting ROS, subsequently preventing hypoxia-induced PASMC proliferation.

Antioxidant Mechanism of Rutin on Hypoxia-Induced Pulmonary Arterial Cell Proliferation

Directory of Open Access Journals (Sweden)

Qian Li

2014-11-01

Full Text Available Reactive oxygen species (ROS are involved in the pathologic process of pulmonary arterial hypertension as either mediators or inducers. Rutin is a type of flavonoid which exhibits significant scavenging properties on oxygen radicals both in vitro and in vivo. In this study, we proposed that rutin attenuated hypoxia-induced pulmonary artery smooth muscle cell (PASMC proliferation by scavenging ROS. Immunofluorescence data showed that rutin decreased the production of ROS, which was mainly generated through mitochondria and NADPH oxidase 4 (Nox4 in pulmonary artery endothelial cells (PAECs. Western blot results provided further evidence on rutin increasing expression of Nox4 and hypoxia-inducible factor-1α (HIF-1α. Moreover, cell cycle analysis by flow cytometry indicated that proliferation of PASMCs triggered by hypoxia was also repressed by rutin. However, N-acetyl-L-cysteine (NAC, a scavenger of ROS, abolished or diminished the capability of rutin in repressing hypoxia-induced cell proliferation. These data suggest that rutin shows a potential benefit against the development of hypoxic pulmonary arterial hypertension by inhibiting ROS, subsequently preventing hypoxia-induced PASMC proliferation.

Microencapsulation of Lefty-secreting engineered cells for pulmonary fibrosis therapy in mice.

Science.gov (United States)

Ma, Hongge; Qiao, Shupei; Wang, Zeli; Geng, Shuai; Zhao, Yufang; Hou, Xiaolu; Tian, Weiming; Chen, Xiongbiao; Yao, Lifen

2017-05-01

Idiopathic pulmonary fibrosis (IPF) is a progressive disease that causes unremitting deposition of extracellular matrix proteins, thus resulting in distortion of the pulmonary architecture and impaired gas exchange. Associated with high morbidity and mortality, IPF is generally refractory to current pharmacological therapies. Lefty A, a potent inhibitor of transforming growth factor-β signaling, has been shown to have promising antifibrotic ability in vitro for the treatment of renal fibrosis and other potential organ fibroses. Here, we determined whether Lefty A can attenuate bleomycin (BLM)-induced pulmonary fibrosis in vivo based on a novel therapeutic strategy where human embryonic kidney 293 (HEK293) cells are genetically engineered with the Lefty A-associated GFP gene. The engineered HEK293 cells were encapsulated in alginate microcapsules and then subcutaneously implanted in ICR mice that had 1 wk earlier been intratracheally administered BLM to induce pulmonary fibrosis. The severity of fibrosis in lung tissue was assessed using pathological morphology and collagen expression to examine the effect of Lefty A released from the microencapsulated cells. The engineered HEK293 cells with Lefty A significantly reduced the expression of connective tissue growth factor and collagen type I mRNA, lessened the morphological fibrotic effects induced by BLM, and increased the expression of matrix metalloproteinase-9. This illustrates that engineered HEK293 cells with Lefty A can attenuate pulmonary fibrosis in vivo, thus providing a novel method to treat human pulmonary fibrotic disease and other organ fibroses. Copyright © 2017 the American Physiological Society.

Mechanical exfoliation of two-dimensional materials

Science.gov (United States)

Gao, Enlai; Lin, Shao-Zhen; Qin, Zhao; Buehler, Markus J.; Feng, Xi-Qiao; Xu, Zhiping

2018-06-01

Two-dimensional materials such as graphene and transition metal dichalcogenides have been identified and drawn much attention over the last few years for their unique structural and electronic properties. However, their rise begins only after these materials are successfully isolated from their layered assemblies or adhesive substrates into individual monolayers. Mechanical exfoliation and transfer are the most successful techniques to obtain high-quality single- or few-layer nanocrystals from their native multi-layer structures or their substrate for growth, which involves interfacial peeling and intralayer tearing processes that are controlled by material properties, geometry and the kinetics of exfoliation. This procedure is rationalized in this work through theoretical analysis and atomistic simulations. We propose a criterion to assess the feasibility for the exfoliation of two-dimensional sheets from an adhesive substrate without fracturing itself, and explore the effects of material and interface properties, as well as the geometrical, kinetic factors on the peeling behaviors and the torn morphology. This multi-scale approach elucidates the microscopic mechanism of the mechanical processes, offering predictive models and tools for the design of experimental procedures to obtain single- or few-layer two-dimensional materials and structures.

Peripheral Nerve Regeneration by Secretomes of Stem Cells from Human Exfoliated Deciduous Teeth.

Science.gov (United States)

Sugimura-Wakayama, Yukiko; Katagiri, Wataru; Osugi, Masashi; Kawai, Takamasa; Ogata, Kenichi; Sakaguchi, Kohei; Hibi, Hideharu

2015-11-15

Peripheral nerve regeneration across nerve gaps is often suboptimal, with poor functional recovery. Stem cell transplantation-based regenerative therapy is a promising approach for axon regeneration and functional recovery of peripheral nerve injury; however, the mechanisms remain controversial and unclear. Recent studies suggest that transplanted stem cells promote tissue regeneration through a paracrine mechanism. We investigated the effects of conditioned media derived from stem cells from human exfoliated deciduous teeth (SHED-CM) on peripheral nerve regeneration. In vitro, SHED-CM-treated Schwann cells exhibited significantly increased proliferation, migration, and the expression of neuron-, extracellular matrix (ECM)-, and angiogenesis-related genes. SHED-CM stimulated neuritogenesis of dorsal root ganglia and increased cell viability. Similarly, SHED-CM enhanced tube formation in an angiogenesis assay. In vivo, a 10-mm rat sciatic nerve gap model was bridged by silicon conduits containing SHED-CM or serum-free Dulbecco's modified Eagle's medium. Light and electron microscopy confirmed that the number of myelinated axons and axon-to-fiber ratio (G-ratio) were significantly higher in the SHED-CM group at 12 weeks after nerve transection surgery. The sciatic functional index (SFI) and gastrocnemius (target muscle) wet weight ratio demonstrated functional recovery. Increased compound muscle action potentials and increased SFI in the SHED-CM group suggested sciatic nerve reinnervation of the target muscle and improved functional recovery. We also observed reduced muscle atrophy in the SHED-CM group. Thus, SHEDs may secrete various trophic factors that enhance peripheral nerve regeneration through multiple mechanisms. SHED-CM may therefore provide a novel therapy that creates a more desirable extracellular microenvironment for peripheral nerve regeneration.

Characterization of exfoliated/delamination kaolinite

International Nuclear Information System (INIS)

Sun, Dewen; Li, Bin; Li, Yanfeng; Yu, Cui; Zhang, Bo; Fei, Huafeng

2011-01-01

A novel and facile approach for the preparation of exfoliated/delamination kaolinite was reported in this study. Kaolinite was mechanochemically activated by grinding with dimethylsulfoxide in a globe mill for different periods of time, and then the activated samples were treated for several hours at 120 o C to obtain the precursors of kaolinite. The resulting materials were characterized by X-ray powder diffraction, scanning electron microscopy, transmission electron microscopy, and X-ray photoelectron spectroscopy. The experimental data indicated that the clay layers were well exfoliated/delamination under mechanochemical effect in a significantly short intercalation time. The expansion of the basal spacing (d 001 ) of raw kaolinite by 0.40 nm pointed out that the hydrogen bonds between adjacent kaolinite layers were partially broken as a result of the intercalation with dimethylsulfoxide.

Pulmonary Function in Patients With Germ Cell Cancer Treated With Bleomycin, Etoposide, and Cisplatin

DEFF Research Database (Denmark)

Lauritsen, Jakob; Kier, Maria Gry Gundgaard; Bandak, Mikkel

2016-01-01

PURPOSE: For patients with germ cell cancer, various pulmonary toxicity risk factors have been hypothesized for treatment with bleomycin, etoposide, and cisplatin (BEP). Because existing studies have shortcomings, we present a large, unselected cohort of patients who have undergone close monitoring...... expiratory volume in 1 second and forced vital capacity remained unchanged after BEP but increased significantly to levels above pretreatment during follow-up. International Germ Cell Cancer Collaborative Group (IGCCCG) prognostic group, mediastinal primary, pulmonary metastases, and smoking all...... PFT. CONCLUSION: After 5 years of follow-up, pulmonary impairment in patients with germ cell cancer who were treated with BEP was limited. Exceptions were patients treated with pulmonary surgery, those who suffered pulmonary embolism, and those in the IGCCCG poor prognostic group....

Pathophysiology and treatment of pulmonary hypertension in sickle cell disease

Science.gov (United States)

Castro, Oswaldo L.; Machado, Roberto F.

2016-01-01

Pulmonary hypertension affects ∼10% of adult patients with sickle cell disease (SCD), particularly those with the homozygous genotype. An increase in pulmonary artery systolic pressure, estimated noninvasively by echocardiography, helps identify SCD patients at risk for pulmonary hypertension, but definitive diagnosis requires right-heart catheterization. About half of SCD-related pulmonary hypertension patients have precapillary pulmonary hypertension with potential etiologies of (1) a nitric oxide deficiency state and vasculopathy consequent to intravascular hemolysis, (2) chronic pulmonary thromboembolism, or (3) upregulated hypoxic responses secondary to anemia, low O2 saturation, and microvascular obstruction. The remainder have postcapillary pulmonary hypertension secondary to left ventricular dysfunction. Although the pulmonary artery pressure in SCD patients with pulmonary hypertension is only moderately elevated, they have a markedly higher risk of death than patients without pulmonary hypertension. Guidelines for diagnosis and management of SCD-related pulmonary hypertension were published recently by the American Thoracic Society. Management of adults with sickle-related pulmonary hypertension is based on anticoagulation for those with thromboembolism; oxygen therapy for those with low oxygen saturation; treatment of left ventricular failure in those with postcapillary pulmonary hypertension; and hydroxyurea or transfusions to raise the hemoglobin concentration, reduce hemolysis, and prevent vaso-occlusive events that cause additional increases in pulmonary pressure. Randomized trials have not identified drugs to lower pulmonary pressure in SCD patients with precapillary pulmonary hypertension. Patients with hemodynamics of pulmonary arterial hypertension should be referred to specialized centers and considered for treatments known to be effective in other forms of pulmonary arterial hypertension. There have been reports that some of these treatments

Micromechanical exfoliation of two-dimensional materials by a polymeric stamp

International Nuclear Information System (INIS)

Costa, M C Ferraz da; Ribeiro, H B; Kessler, F; Souza, E A T de; Fechine, G J M

2016-01-01

In this work, an alternative technique to the traditional micromechanical exfoliation of two-dimensional materials is proposed, consisting of isolated flakes of graphite and molybdenum disulphide onto polymeric surfaces films. The set made up of polymer and flakes is fabricated by using a hot-press machine called polymeric stamp. The polymeric stamp was used to allocate flakes and also to allow the exfoliation process to take place just in one face of isolated flake. Optical microscopy, Raman spectroscopy and photoluminescence spectroscopy results showed that multilayers, bilayers and single layers of graphene and MoS 2 were obtained by using a polymeric stamp as tool for micromechanical exfoliation. These crystals were more easily found because the exfoliation process concentrates them in well-defined locations. The results prove the effectiveness of the method by embedding two-dimensional materials into polymers to fabricate fewer layers crystals in a fast, economic and clean way. (paper)

Micromechanical exfoliation of two-dimensional materials by a polymeric stamp

Science.gov (United States)

Ferraz da Costa, M. C.; Ribeiro, H. B.; Kessler, F.; de Souza, E. A. T.; Fechine, G. J. M.

2016-02-01

In this work, an alternative technique to the traditional micromechanical exfoliation of two-dimensional materials is proposed, consisting of isolated flakes of graphite and molybdenum disulphide onto polymeric surfaces films. The set made up of polymer and flakes is fabricated by using a hot-press machine called polymeric stamp. The polymeric stamp was used to allocate flakes and also to allow the exfoliation process to take place just in one face of isolated flake. Optical microscopy, Raman spectroscopy and photoluminescence spectroscopy results showed that multilayers, bilayers and single layers of graphene and MoS2 were obtained by using a polymeric stamp as tool for micromechanical exfoliation. These crystals were more easily found because the exfoliation process concentrates them in well-defined locations. The results prove the effectiveness of the method by embedding two-dimensional materials into polymers to fabricate fewer layers crystals in a fast, economic and clean way.

Erythropoietin Attenuates Pulmonary Vascular Remodeling in Experimental Pulmonary Arterial Hypertension through Interplay between Endothelial Progenitor Cells and Heme Oxygenase

OpenAIRE

van Loon, Rosa Laura E; Bartelds, Beatrijs; Wagener, Frank A D T G; Affara, Nada; Mohaupt, Saffloer; Wijnberg, Hans; Pennings, Sebastiaan W C; Takens, Janny; Berger, Rolf M F

2015-01-01

BACKGROUND: Pulmonary arterial hypertension (PAH) is a pulmonary vascular disease with a high mortality, characterized by typical angio-proliferative lesions. Erythropoietin (EPO) attenuates pulmonary vascular remodeling in PAH. We postulated that EPO acts through mobilization of endothelial progenitor cells (EPCs) and activation of the cytoprotective enzyme heme oxygenase-1 (HO-1). METHODS: Rats with flow-associated PAH, resembling pediatric PAH, were treated with HO-1 inducer EPO in the pre...

Erythropoietin Attenuates Pulmonary Vascular Remodeling in Experimental Pulmonary Arterial Hypertension through Interplay between Endothelial Progenitor Cells and Heme Oxygenase

OpenAIRE

van Loon, Rosa Laura E.; Bartelds, Beatrijs; Wagener, Frank A. D. T. G.; Affara, Nada; Mohaupt, Saffloer; Wijnberg, Hans; Pennings, Sebastiaan W. C.; Takens, Janny; Berger, Rolf M. F.

2015-01-01

Background Pulmonary arterial hypertension (PAH) is a pulmonary vascular disease with a high mortality, characterized by typical angio-proliferative lesions. Erythropoietin (EPO) attenuates pulmonary vascular remodeling in PAH. We postulated that EPO acts through mobilization of endothelial progenitor cells (EPCs) and activation of the cytoprotective enzyme heme oxygenase-1 (HO-1). Methods Rats with flow-associated PAH, resembling pediatric PAH, were treated with HO-1 inducer EPO i...

Exfoliation of graphene flake from SiC substrate using hydrogen injection; a first-principle study

Science.gov (United States)

Lee, Bora; Han, Seungwu; Kim, Yong-Sung

2009-03-01

Recently there is an immense interest in studying graphene for investigating its unique electronic properties as well as practical applications to nanoscale devices. Up to now there are two methods to obtain graphene layers. The first one is a mechanical method in which the single graphene sheet is split off the bulk graphite crystals using adhesives. The other method is graphitization of SiC surfaces by annealing at elevated temperatures. Even though the latter approach can provide a graphene layer in a more controlled way, the exfoliation of the graphene layer still poses a big challenge. In this presentation, based on the first-principles results, we propose a novel exfoliation method using hydrogen. As a model system, the 6H-SiC(0001) 4x4 cell is used, which corresponds to the 3x3 graphene cell. We calculate the binding energy of single hydrogen atom in various places; above and below graphene surface and inside the first SiC layer. The binding energies of hydrogen are calculated for different coverages. It is found that at high coverages, the hydrogen atoms prefer to bind below the graphene surface, cutting the graphene-SiC bonds. This means that the graphene can be exfoliated in the hydrogen-rich environment. The detailed analysis including the electronic structures will be presented.

Chromosomal damage and apoptosis analysis in exfoliated oral epithelial cells from mouthwash and alcohol users

Science.gov (United States)

Rocha, Rodrigo dos Santos; Meireles, José Roberto Cardoso; de Moraes Marcílio Cerqueira, Eneida

2014-01-01

Chromosomal damage and apoptosis were analyzed in users of mouthwash and/or alcoholic beverages, using the micronucleus test on exfoliated oral mucosa cells. Samples from four groups of 20 individuals each were analyzed: three exposed groups (EG1, EG2 and EG3) and a control group (CG). EG1 comprised mouthwash users; EG2 comprised drinkers, and EG3 users of both mouthwashes and alcoholic beverages. Cell material was collected by gently scraping the insides of the cheeks. Then the cells were fixed in a methanol/acetic acid (3:1) solution and stained and counterstained, respectively, with Schiff reactive and fast green. Endpoints were computed on 2,000 cells in a blind test. Statistical analysis showed that chromosomal damage and apoptosis were significantly higher in individuals of groups EG1 and EG3 than in controls (p < 0.005 and p < 0.001, respectively). No significant difference in chromosomal damage and apoptosis was observed between the exposed groups. In EG2, only the occurrence of apoptosis was significantly higher than in the controls. These results suggest that mouthwashes alone or in association with alcoholic drinks induce genotoxic effects, manifested as chromosomal damage and apoptosis. They also suggest that alcoholic drinks are effective for stimulating the process of apoptosis. However, these data need to be confirmed in larger samples. PMID:25505845

Lysophosphatidic acid generation by pulmonary NKT cell ENPP-2/autotaxin exacerbates hyperoxic lung injury.

Science.gov (United States)

Nowak-Machen, Martina; Lange, Martin; Exley, Mark; Wu, Sherry; Usheva, Anny; Robson, Simon C

2015-12-01

Hyperoxia is still broadly used in clinical practice in order to assure organ oxygenation in critically ill patients, albeit known toxic effects. In this present study, we hypothesize that lysophosphatidic acid (LPA) mediates NKT cell activation in a mouse model of hyperoxic lung injury. In vitro, pulmonary NKT cells were exposed to hyperoxia for 72 h, and the induction of the ectonucleotide pyrophosphatase/phosphodiesterase 2 (ENPP-2) was examined and production of lysophosphatidic acid (LPA) was measured. In vivo, animals were exposed to 100 % oxygen for 72 h and lungs and serum were harvested. Pulmonary NKT cells were then incubated with the LPA antagonist Brp-LPA. Animals received BrP-LPA prior to oxygen exposure. Autotaxin (ATX, ENPP-2) was significantly up-regulated on pulmonary NKT cells after hyperoxia (p NKT cells. LPA levels were significantly reduced by incubating NKT cells with LPA-BrP during oxygen exposure (p NKT cell numbers in vivo. BrP-LPA injection significantly improved survival as well as significantly decreased lung injury and lowered pulmonary NKT cell numbers. We conclude that NKT cell-induced hyperoxic lung injury is mediated by pro-inflammatory LPA generation, at least in part, secondary to ENPP-2 up-regulation on pulmonary NKT cells. Being a potent LPA antagonist, BrP-LPA prevents hyperoxia-induced lung injury in vitro and in vivo.

Adult Lung Spheroid Cells Contain Progenitor Cells and Mediate Regeneration in Rodents With Bleomycin-Induced Pulmonary Fibrosis.

Science.gov (United States)

Henry, Eric; Cores, Jhon; Hensley, M Taylor; Anthony, Shirena; Vandergriff, Adam; de Andrade, James B M; Allen, Tyler; Caranasos, Thomas G; Lobo, Leonard J; Cheng, Ke

2015-11-01

Lung diseases are devastating conditions and ranked as one of the top five causes of mortality worldwide according to the World Health Organization. Stem cell therapy is a promising strategy for lung regeneration. Previous animal and clinical studies have focused on the use of mesenchymal stem cells (from other parts of the body) for lung regenerative therapies. We report a rapid and robust method to generate therapeutic resident lung progenitors from adult lung tissues. Outgrowth cells from healthy lung tissue explants are self-aggregated into three-dimensional lung spheroids in a suspension culture. Without antigenic sorting, the lung spheroids recapitulate the stem cell niche and contain a natural mixture of lung stem cells and supporting cells. In vitro, lung spheroid cells can be expanded to a large quantity and can form alveoli-like structures and acquire mature lung epithelial phenotypes. In severe combined immunodeficiency mice with bleomycin-induced pulmonary fibrosis, intravenous injection of human lung spheroid cells inhibited apoptosis, fibrosis, and infiltration but promoted angiogenesis. In a syngeneic rat model of pulmonary fibrosis, lung spheroid cells outperformed adipose-derived mesenchymal stem cells in reducing fibrotic thickening and infiltration. Previously, lung spheroid cells (the spheroid model) had only been used to study lung cancer cells. Our data suggest that lung spheroids and lung spheroid cells from healthy lung tissues are excellent sources of regenerative lung cells for therapeutic lung regeneration. The results from the present study will lead to future human clinical trials using lung stem cell therapies to treat various incurable lung diseases, including pulmonary fibrosis. The data presented here also provide fundamental knowledge regarding how injected stem cells mediate lung repair in pulmonary fibrosis. ©AlphaMed Press.

Enhanced pulmonary toxicity with bleomycin and radiotherapy in oat cell lung cancer

International Nuclear Information System (INIS)

Einhorn, L.; Krause, M.; Hornback, N.; Furnas, B.

1976-01-01

In a recently completed study, combination chemotherapy consisting of bleomycin, adriamycin, cyclophosphamide, and vincristine was given to 29 patients with oat cell lung cancer. There were no cases of pulmonary fibrosis in these 29 patients. Although several of these patients had prior radiotherapy, none had concomitant radiotherapy and chemotherapy. This same four-drug chemotherapy regimen was combined with concomitant radiotherapy in 13 patients with oat cell lung cancer. There were three cases of fatal pulmonary fibrosis and two other cases of clinically significant pulmonary fibrosis. All five cases of pulmonary fibrosis occurred several weeks after completion of a six-week course of bleomycin (total dosage 90 units). It is concluded that bleomycin cannot be safely administered while patients are receiving radiotherapy of the lung

[Regulation of airway stem cell proliferation in idiopathic pulmonary fibrosis].

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Yang, S X; Wu, Q; Sun, X; Li, X; Li, K; Xu, L; Li, Y; Zhang, Q Y; Zhang, Y C; Chen, H Y

2016-09-01

To investigate the effect of fibroblasts on regulating airway stem cell proliferation in idiopathic pulmonary fibrosis. Lung cell suspension was prepared from β-actin-GFP mice. Airway stem cells were obtained by fluorescence activated cell sorting and co-cultured with lung fibroblasts. The fibroblasts were treated with TGF-β inhibitor SB43142. The expression of growth factors FGF1/2 and the effect of FGF1/2 on stem cell proliferation were observed. The cloning efficiency of airway stem cells, when co-cultured with normal lung fibroblast cells for 8 days, was (3.5±1.1)%, while the cloning efficiency was reduced to (0.04±0.04)% when co-cultured with lung fibroblasts from idiopathic pulmonary fibrosis patients. The difference between the 2 groups was statistically significant(P=0.002 5). TGF-β receptor inhibitor SB431542 increased lung fibroblast growth factors FGF1/2 expression.FGF1 mRNA expression was increased to the experimental group 0.005 5 from 0.000 2 in the control group.FGF2 mRNA expression of the amount raised to the experimental group 0.000 15 from 0.000 8 in the control group.FGF1/2 promoted the growth of airway stem cells. After FGF1/2 was co-cultured with normal lung fibroblast cells for 8 days, the cloning efficiency of airway stem cells was (0.3±0.1)%. During the development of idiopathic pulmonary fibrosis, fibroblast secreted FGF1/2 regulate airway stem cell proliferation.

Swelling, intercalation, and exfoliation behavior of layered ruthenate derived from layered potassium ruthenate

International Nuclear Information System (INIS)

Fukuda, Katsutoshi; Kato, Hisato; Sato, Jun; Sugimoto, Wataru; Takasu, Yoshio

2009-01-01

The intercalation chemistry of a layered protonic ruthenate, H 0.2 RuO 2.1 .nH 2 O, derived from a layered potassium ruthenate was studied in detail. Three phases with different hydration states were isolated, H 0.2 RuO 2.1 .nH 2 O (n=∼0, 0.5, 0.9), and its reactivity with tetrabutylammonium ions (TBA + ) was considered. The layered protonic ruthenate mono-hydrate readily reacted with TBA + , affording direct intercalation of bulky tetrabutylammonium ions into the interlayer gallery. Fine-tuning the reaction conditions allowed exfoliation of the layered ruthenate into elementary nanosheets and thereby a simplified one-step exfoliation was achieved. Microscopic observation by atomic force microscopy and transmission electron microscopy clearly showed the formation of unilamellar sheets with very high two-dimensional anisotropy, a thickness of only 1.3±0.1 nm. The nanosheets were characterized by two-dimensional crystallites with the oblique cell of a=0.5610(8) nm, b=0.5121(6) nm and γ=109.4(2) o on the basis of in-plane diffraction analysis. - Graphical abstract: Layered protonic ruthenate derived from a potassium form was directly reacted with bulky tetrabutylammonium ions to trigger exfoliation into nanosheets as long as it is highly hydrated.

Hypoxic contraction of cultured pulmonary vascular smooth muscle cells

International Nuclear Information System (INIS)

Murray, T.R.; Chen, L.; Marshall, B.E.; Macarak, E.J.

1990-01-01

The cellular events involved in generating the hypoxic pulmonary vasoconstriction response are not clearly understood, in part because of the multitude of factors that alter pulmonary vascular tone. The goal of the present studies was to determine if a cell culture preparation containing vascular smooth muscle (VSM) cells could be made to contract when exposed to a hypoxic atmosphere. Cultures containing only fetal bovine pulmonary artery VSM cells were assessed for contractile responses to hypoxic stimuli by two methods. In the first, tension forces generated by cells grown on a flexible growth surface (polymerized polydimethyl siloxane) were manifested as wrinkles and distortions of the surface under the cells. Wrinkling of the surface was noted to progressively increase with time as the culture medium bathing the cells was made hypoxic (PO2 approximately 25 mmHg). The changes were sometimes reversible upon return to normoxic conditions and appeared to be enhanced in cells already exhibiting evidence of some baseline tone. Repeated passage in culture did not diminish the hypoxic response. Evidence for contractile responses to hypoxia was also obtained from measurements of myosin light chain (MLC) phosphorylation. Conversion of MLC to the phosphorylated species is an early step in the activation of smooth muscle contraction. Lowering the PO2 in the culture medium to 59 mmHg caused a 45% increase in the proportion of MLC in the phosphorylated form as determined by two-dimensional gel electrophoresis. Similarly, cultures preincubated for 4 h with 32P and then exposed to normoxia or hypoxia for a 5-min experimental period showed more than twice as much of the label in MLCs of the hypoxic cells

ITE inhibits growth of human pulmonary artery endothelial cells.

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Pang, Ling-Pin; Li, Yan; Zou, Qing-Yun; Zhou, Chi; Lei, Wei; Zheng, Jing; Huang, Shi-An

2017-10-01

Pulmonary arterial hypertension (PAH), a deadly disorder is associated with excessive growth of human pulmonary artery endothelial (HPAECs) and smooth muscle (HPASMCs) cells. Current therapies primarily aim at promoting vasodilation, which only ameliorates clinical symptoms without a cure. 2-(1'H-indole-3'-carbonyl)-thiazole-4-carboxylic acid methyl ester (ITE) is an endogenous aryl hydrocarbon receptor (AhR) ligand, and mediates many cellular function including cell growth. However, the roles of ITE in human lung endothelial cells remain elusive. Herein, we tested a hypothesis that ITE inhibits growth of human pulmonary artery endothelial cells via AhR. Immunohistochemistry was performed to localize AhR expression in human lung tissues. The crystal violet method and MTT assay were used to determine ITE's effects on growth of HPAECs. The AhR activation in HPAECs was confirmed using Western blotting and RT-qPCR. The role of AhR in ITE-affected proliferation of HPAECs was assessed using siRNA knockdown method followed by the crystal violet method. Immunohistochemistry revealed that AhR was present in human lung tissues, primarily in endothelial and smooth muscle cells of pulmonary veins and arteries, as well as in bronchial and alveolar sac epithelia. We also found that ITE dose- and time-dependently inhibited proliferation of HPAECs with a maximum inhibition of 83% at 20 µM after 6 days of treatment. ITE rapidly decreased AhR protein levels, while it increased mRNA levels of cytochrome P450 (CYP), family 1, member A1 (CYP1A1) and B1 (CYP1B1), indicating activation of the AhR/CYP1A1 and AhR/CYP1B1 pathways in HPAECs. The AhR siRNA significantly suppressed AhR protein expression, whereas it did not significantly alter ITE-inhibited growth of HPAECs. ITE suppresses growth of HPAECs independent of AhR, suggesting that ITE may play an important role in preventing excessive growth of lung endothelial cells.

The distribution of immunomodulatory cells in the lungs of patients with idiopathic pulmonary fibrosis

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Nuovo, Gerard J.; Hagood, James S.; Magro, Cynthia M.; Chin, Nena; Kapil, Rubina; Davis, Luke; Marsh, Clay B.; Folcik, Virginia A.

2011-01-01

We have characterized the immune system involvement in the disease processes of idiopathic pulmonary fibrosis in novel ways. To do so, we analyzed lung tissue from 21 cases of idiopathic pulmonary fibrosis and 21 (non-fibrotic, non-cancerous) controls for immune cell and inflammation-related markers. The immunohistochemical analysis of the tissue was grouped by patterns of severity in disease pathology. There were significantly greater numbers of CD68+ and CD80+ cells, and significantly fewer CD3+, CD4+, and CD45RO+ cells in areas of relatively (histologically) normal lung in biopsies from idiopathic pulmonary fibrosis patients compared to controls. In zones of active disease, characterized by epithelial cell regeneration and fibrosis, there were significantly more cells expressing CD4, CD8, CD20, CD68, CD80, CCR6, S100, IL-17, tumor necrosis factor-α, and retinoic acid-related orphan receptors compared to histologically normal lung areas from idiopathic pulmonary fibrosis patients. Inflammation was implicated in these active regions by the cells that expressed retinoid orphan receptor-α, -β, and -γ, CCR6, and IL-17. The regenerating epithelial cells predominantly expressed these pro-inflammatory molecules, as evidenced by co-expression analyses with epithelial cytokeratins. Macrophages in pseudo-alveoli and CD3+ T cells in the fibrotic interstitium also expressed IL-17. Co-expression of IL-17 with retinoid orphan receptors, and epithelial cytoskeletal proteins, CD68, and CD3 in epithelial cells, macrophages, and T-cells, respectively, confirmed the production of IL-17 by these cell types. There was little staining for Foxp3, CD56, or CD34 in any idiopathic pulmonary fibrosis lung regions. The fibrotic regions had fewer immune cells overall. In summary, our study shows participation of innate and adaptive mononuclear cells in active-disease regions of idiopathic pulmonary fibrosis lung, where the regenerating epithelial cells appear to propagate inflammation

Use of the fluorescent micronucleus assay to detect the genotoxic effects of radiation and arsenic exposure in exfoliated human epithelial cells

International Nuclear Information System (INIS)

Moore, L.E.; Warner, M.L.; Smith, A.H.

1996-01-01

The exfoliated cell micronucleus (MN) assay using fluorescent in situ hybridization (FISH) with a centromeric probe is a rapid method for determining the mechanism of MN formation in epithelial tissues exposed to carcinogenic agents. Here, we describe the use of this assay to detect the presence or absence of centromeric DNA in MN induced in vivo by radiation therapy and chronic arsenic (As) ingestion. We examined the buccal cells of an individual receiving 6,500 rads of photon radiation to the head and neck. Exfoliated cells were collected before, during, and after treatment. After radiation exposure a 16.6-fold increase in buccal cell MN frequency was seen. All induced MN were centromere negative (MN-) resulting from chromosome breakage. This finding is consistent with the clastogenic action of radiation and confirmed the reliability of the method. Three weeks post-therapy, MN frequencies returned to baseline. The assay was used on 18 people chronically exposed to high levels of inorganic arsenic (In-As) in drinking water (average level, 1,312 μg As/L) and 18 matched controls (average level, 16 μg As/L). The combined increase in MN frequency was 1.8-fold (P = 0.001, Fisher's exact test). Frequencies of micronuclei containing acentric fragments (MN-) and those containing whole chromosomes (MN+) both increased, suggesting that arsenic may have both clastogenic and weak aneuploidogenic properties in vivo. After stratification on sex, the effect was stronger in male than in female bladder cells. In males the MN-frequency increased 2.06-fold (P =0.07) while the frequency of MN+ increased 1.86-fold (P = 0.08). In addition, the frequencies of MN and MN+ were positively associated with urinary arsenic and its metabolites. The association was stronger for micronuclei containing acentric fragments. By using FISH with centromeric probes, the mechanism of chemically induced genotoxicity can not be determined in epithelial tissues. 35 refs., 4 tabs

Fabrication of two-dimensional nanosheets via water freezing expansion exfoliation

International Nuclear Information System (INIS)

Li, Chen; Wang, Tailin; Wu, Yongzhong; Ma, Fukun; Zhao, Gang; Hao, Xiaopeng

2014-01-01

Layered materials, if exfoliated effectively, will exhibit several unique properties, offering great potential for diverse applications. To this end, in this study, we develop a novel, universal, and environmentally friendly method named as ‘water freezing expansion exfoliation’ for producing two-dimensional nanosheets. This method exploits the expansion in the volume of water upon freezing. When the water freezing expansion condition is reproduced in layered materials, the layers exfoliate to overcome the van der Waals force between them. The expansion process is performed by repeated cycling between 4 °C and −20 °C to effectively exfoliate layered materials of graphite, hexagonal boron nitride (h-BN), MoS 2 and WS 2 . Systematic characterization of the samples thus obtained using electron microscopy and optical studies substantiate the formation of thin flakes (graphene, h-BN, MoS 2 , and WS 2 nanosheets). The method demonstrated in this study is cost-effective and does not demand sophisticated equipment and stringent high temperature conditions. Given this general applicability, this method holds great promise for exfoliating layered materials that are sensitive to elevated temperature. (paper)

Photoluminescence of MoS2 Prepared by Effective Grinding-Assisted Sonication Exfoliation

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Jing-Yuan Wu

2014-01-01

Full Text Available Exfoliation of bulk molybdenum disulfide (MoS2 using sonication in appropriate solvent is a promising route to large-scale preparation of few-layered or monolayered crystals. Grinding-assisted sonication exfoliation was used for preparing monolayered MoS2 nanosheets from natural mineral molybdenite. By controlling the sonication time, larger crystallites could be further exfoliated to smaller as well as thinner nanosheets without damaging their structures. The concentration of 1.6 mg mL−1 of final solution could be achieved. Several microscopic techniques like scanning electron microscopy, transmission electron microscopy, and atomic force microscopy were employed to evaluate the exfoliation results. Strong photoluminescence with the peak centered at 440 nm was also observed in the resulting dispersion which included several small lateral-sized (~3 nm nanostructures.

Modulation of cGMP by human HO-1 retrovirus gene transfer in pulmonary microvessel endothelial cells.

Science.gov (United States)

Abraham, Nader G; Quan, Shuo; Mieyal, Paul A; Yang, Liming; Burke-Wolin, Theresa; Mingone, Christopher J; Goodman, Alvin I; Nasjletti, Alberto; Wolin, Michael S

2002-11-01

Carbon monoxide (CO) stimulates guanylate cyclase (GC) and increases guanosine 3',5'-cyclic monophosphate (cGMP) levels. We transfected rat-lung pulmonary endothelial cells with a retrovirus-mediated human heme oxygenase (hHO)-1 gene. Pulmonary cells that expressed hHO-1 exhibited a fourfold increase in HO activity associated with decreases in the steady-state levels of heme and cGMP without changes in soluble GC (sGC) and endothelial nitric oxide synthase (NOS) proteins or basal nitrite production. Heme elicited significant increases in CO production and intracellular cGMP levels in both pulmonary endothelial and pulmonary hHO-1-expressing cells. N(omega)-nitro-L-arginine methyl ester (L-NAME), an inhibitor of NOS, significantly decreased cGMP levels in heme-treated pulmonary endothelial cells but not heme-treated hHO-1-expressing cells. In the presence of exogenous heme, CO and cGMP levels in hHO-1-expressing cells exceeded the corresponding levels in pulmonary endothelial cells. Acute exposure of endothelial cells to SnCl2, which is an inducer of HO-1, increased cGMP levels, whereas chronic exposure decreased heme and cGMP levels. These results indicate that prolonged overexpression of HO-1 ultimately decreases sGC activity by limiting the availability of cellular heme. Heme activates sGC and enhances cGMP levels via a mechanism that is largely insensitive to NOS inhibition.

Indoleamine 2,3-Dioxygenase Is Dispensable for The Immunomodulatory Function of Stem Cells from Human Exfoliated Deciduous Teeth.

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Alipour, Razieh; Masoumi Karimi, Masoumeh; Hashemi-Beni, Batool; Adib, Minoo; Sereshki, Nasrin; Sadeghi, Farzaneh

2017-01-01

In this study, we sought to better understand the immunoregulatory function of stem cells derived from human exfoliated deciduous teeth (SHED). We studied the role of the interferon gamma (IFN-γ)-indoleamine 2,3-dioxygenase (IDO)-axis in immunoregulation of SHED compared to bone marrow derived mesenchymal stem cells (BMMSCs) under the same conditions. In this cross-sectional study, recently isolated human T cells were stimulated either by mitogen or inactivated allogeneic peripheral blood mononuclear cells (PBMCs). These T cells were subsequently co-cultured with, either SHED or BMMSCs in the presence or absence of 1-methyl-tryptophan (1-MT) or neutralizing anti- human-IFN-γ antibodies. In all co-cultures we evaluated lymphocyte activation as well as IDO activity. SHED, similar to conventional BMMSCs, had anti-proliferative effects on stimulated T cells and reduced their cytokine production. This property of SHED and BMMSCs was changed by IFN-γ neutralization. We detected IDO in the immunosuppressive supernatant of all co-cultures. Removal of IDO decreased the immunosuppression of BMMSCs. SHED, like BMMSCs, produced the IDO enzyme. Although IFN-γ is one of inducer of IDO production in SHED, these cells were not affected by IFN-γ in the same manner as BMMSCs. Unlike BMMSCs, the IDO enzyme did not contribute to their immunosuppression and might have other cell-type specific roles.

Induction of expression of two phenotypic markers of pulmonary type II cells in a cultured cell line

International Nuclear Information System (INIS)

Henderson, R.F.; Waide, J.J.; Scott, G.G.

1994-01-01

The functions of pulmonary type II cells, such as synthesis of pulmonary surfactant and metabolism of inhaled xenobiotics, can be studied in primary isolates of lung cells. However, isolated type II cells, when cultured, quickly lose the phenotypic expressions characteristics of type II cells, including surfactant lipid and protein synthesis and alkaline phosphatase (AP) activity. A cultured cell line that maintained expression of type II cell markers of differentiation would be advantageous for the study of such functions as surfactant synthesis and secretion. Such a cell line would allow generation of a large number of homogeneous cells for study. The purpose of the current study was to induce markers of differentiated type II cells in a cultured cell line to facilitate studies of factors that control surfactant synthesis and secretion

Liquid-Phase Exfoliation of Phosphorene: Design Rules from Molecular Dynamics Simulations.

Science.gov (United States)

Sresht, Vishnu; Pádua, Agílio A H; Blankschtein, Daniel

2015-08-25

The liquid-phase exfoliation of phosphorene, the two-dimensional derivative of black phosphorus, in the solvents dimethyl sulfoxide (DMSO), dimethylformamide (DMF), isopropyl alcohol, N-methyl-2-pyrrolidone, and N-cyclohexyl-2-pyrrolidone is investigated using three molecular-scale "computer experiments". We modeled solvent-phosphorene interactions using an atomistic force field, based on ab initio calculations and lattice dynamics, that accurately reproduces experimental mechanical properties. We probed solvent molecule ordering at phosphorene/solvent interfaces and discovered that planar molecules such as N-methyl-2-pyrrolidone preferentially orient parallel to the interface. We subsequently measured the energy required to peel a single phosphorene monolayer from a stack of black phosphorus and analyzed the role of "wedges" of solvent molecules intercalating between phosphorene sheets in initiating exfoliation. The exfoliation efficacy of a solvent is enhanced when either molecular planarity "sharpens" this molecular wedge or strong phosphorene-solvent adhesion stabilizes the newly exposed phosphorene surfaces. Finally, we examined the colloidal stability of exfoliated flakes by simulating their aggregation and showed that dispersion is favored when the cohesive energy between the molecules in the solvent monolayer confined between the phosphorene sheets is high (as with DMSO) and is hindered when the adhesion between these molecules and phosphorene is strong; the molecular planarity in solvents like DMF enhances the cohesive energy. Our results are consistent with, and provide a molecular context for, experimental exfoliation studies of phosphorene and other layered solids, and our molecular insights into the significant role of solvent molecular geometry and ordering should complement prevalent solubility-parameter-based approaches in establishing design rules for effective nanomaterial exfoliation media.

Osteoblastic differentiation of stem cells from human exfoliated deciduous teeth induced by thermosensitive hydrogels with strontium phosphate

Energy Technology Data Exchange (ETDEWEB)

Su, Wen-Ta, E-mail: f10549@ntut.edu.tw [Department of Chemical Engineering and Biotechnology National Taipei University of Technology, Taipei, Taiwan (China); Chou, Wei-Ling [Department of Chemical Engineering and Biotechnology National Taipei University of Technology, Taipei, Taiwan (China); Chou, Chih-Ming [Department of Biochemistry, Taipei Medical University, Taipei, Taiwan (China)

2015-07-01

Stem cells from human exfoliated deciduous teeth (SHEDs) are a novel source of multi-potential stem cells for tissue engineering because of their potential to differentiate into multiple cell lineages. Strontium exhibits an important function in bone remodeling because it can simulate bone formation and decrease bone resorption. Hydrogels can mimic the natural cellular environment. The association of hydrogels with cell viability is determined using biological tests, including rheological experiments. In this study, osteogenic differentiation was investigated through SHED encapsulation in hydrogels containing strontium phosphate. Results of 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide (MTT) and proliferating cell nuclear antigen (PCNA) immunofluorescence staining indicated that the cells grew well and SHEDs proliferated in the hydrogels. Strontium-loaded chitosan-based hydrogels induced the biomineralization and high expression of alkaline phosphatase. Moreover, the expression levels of bone-related genes, including type-I collagen, Runx2, osteopontin (OP), and osteonectin (ON), were up-regulated during the osteogenic differentiation of SHEDs. This study demonstrated that strontium can be an effective inducer of osteogenesis for SHEDs. Elucidating the function of bioceramics (such as strontium) is useful in designing and developing strategies for bone tissue engineering. - Highlights: • SHEDs have been considered as alternative sources of adult stem cells in tissue engineering. • Strontium phosphate can enhance the osteogenic differentiation of SHEDs. • Hydrogels can mimic the natural cellular environment. • Bioceramics (such as strontium) is useful in designing and developing strategies for bone tissue engineering.

Exfoliated MoS2 nanosheets as efficient catalysts for electrochemical hydrogen evolution

International Nuclear Information System (INIS)

Ji, Shanshan; Yang, Zhe; Zhang, Chao; Liu, Zhenyan; Tjiu, Weng Weei; Phang, In Yee; Zhang, Zheng; Pan, Jisheng; Liu, Tianxi

2013-01-01

Graphical abstract: An efficient electrocatalyst for hydrogen evolution has been developed based on exfoliation of bulk MoS 2 crystals via a direct dispersion and ultrasonication method. Drop-casting method is used to fabricate the exfoliated MoS 2 nanosheets modified glass carbon electrode (E-MoS 2 /GCE) with various loadings. The E-MoS 2 /GCE with electrode loading of 48 μg cm −1 exhibits high catalytic activity for hydrogen evolution with a low overpotential (−0.12 V) and a high current density (1.26 mA cm −2 , at η = 150 mV). -- Highlights: • Two-dimensional MoS 2 nanosheets have been obtained by exfoliation of bulk MoS 2 crystals. • Exfoliated MoS 2 nanosheets show high electrocatalytic activity for H 2 production. • This study provides a new approach for renewable and economic H 2 production. -- Abstract: An efficient electrocatalyst for hydrogen evolution has been developed based on liquid exfoliation of bulk MoS 2 via a direct dispersion and ultrasonication method. Transmission electron microscopy and atomic force microscopy measurements show that the exfoliated MoS 2 consists of two-dimensional nanosheets. The exfoliated MoS 2 nanosheets modified glass carbon electrode (E-MoS 2 /GCE) with various loadings is fabricated via a drop-casting method. The electrocatalytic activity of E-MoS 2 /GCE toward hydrogen evolution reaction is examined using linear sweep voltammetry. It is shown that the E-MoS 2 /GCE with an electrode loading of 48 μg cm −2 exhibits a high catalytic activity for hydrogen evolution with a low overpotential (−0.12 V) and a high current density (1.26 mA cm −2 , at η = 150 mV)

Covalent functionalization and passivation of exfoliated black phosphorus via aryl diazonium chemistry

Science.gov (United States)

Ryder, Christopher R.; Wood, Joshua D.; Wells, Spencer A.; Yang, Yang; Jariwala, Deep; Marks, Tobin J.; Schatz, George C.; Hersam, Mark C.

2016-06-01

Functionalization of atomically thin nanomaterials enables the tailoring of their chemical, optical and electronic properties. Exfoliated black phosphorus (BP)—a layered two-dimensional semiconductor—exhibits favourable charge-carrier mobility, tunable bandgap and highly anisotropic properties, but it is chemically reactive and degrades rapidly in ambient conditions. Here we show that covalent aryl diazonium functionalization suppresses the chemical degradation of exfoliated BP even after three weeks of ambient exposure. This chemical modification scheme spontaneously forms phosphorus-carbon bonds, has a reaction rate sensitive to the aryl diazonium substituent and alters the electronic properties of exfoliated BP, ultimately yielding a strong, tunable p-type doping that simultaneously improves the field-effect transistor mobility and on/off current ratio. This chemical functionalization pathway controllably modifies the properties of exfoliated BP, and thus improves its prospects for nanoelectronic applications.

Evaluation of profile and functionality of memory T cells in pulmonary tuberculosis.

Science.gov (United States)

Tonaco, Marcela M; Moreira, Jôsimar D; Nunes, Fernanda F C; Loures, Cristina M G; Souza, Larissa R; Martins, Janaina M; Silva, Henrique R; Porto, Arthur Henrique R; Toledo, Vicente Paulo C P; Miranda, Silvana S; Guimarães, Tânia Mara P D

2017-12-01

The cells T CD4+ T and CD8+ can be subdivided into phenotypes naïve, T of central memory, T of effector memory and effector, according to the expression of surface molecules CD45RO and CD27. The T lymphocytes are cells of long life with capacity of rapid expansion and function, after a new antigenic exposure. In tuberculosis, it was found that specific memory T cells are present, however, gaps remain about the role of such cells in the disease immunology. In this study, the phenotypic profile was analyzed and characterized the functionality of CD4+ T lymphocytes and CD8+ T cells of memory and effector, in response to specific stimuli in vitro, in patients with active pulmonary TB, compared to individuals with latent infection with Mycobacterium tuberculosis the ones treated with pulmonary TB. It was observed that the group of patients with active pulmonary tuberculosis was the one which presented the highest proportion of cells T CD4+ of central memory IFN-ɣ+ e TNF-α+, suggesting that in TB, these T of central memory cells would have a profile of protective response, being an important target of study for the development of more effective vaccines; this group also developed lower proportion of CD8+ T effector lymphocytes than the others, a probable cause of specific and less effective response against the bacillus in these individuals; the ones treated for pulmonary tuberculosis were those who developed higher proportion of T CD4+ of memory central IL-17+ cells, indicating that the stimulation of long duration, with high antigenic load, followed by elimination of the pathogen, contribute to more significant generation of such cells; individuals with latent infection by M. tuberculosis and treated for pulmonary tuberculosis, showed greater response of CD8+ T effector lymphocytes IFN-ɣ+ than the controls, suggesting that these cells, as well as CD4+ T lymphocytes, have crucial role of protection against M. tuberculosis. These findings have contributed to a better

The role of receptor-mediated T-cells activation disorders in pulmonary tuberculosis

Directory of Open Access Journals (Sweden)

Irina E. Esimova

2017-01-01

Full Text Available Aim. To analyze the peculiarities and mechanisms of receptor-mediated T-lymphocytes disorders in different clinical forms of pulmonary tuberculosis.Materials and мethods. The study involved 116 patients with first diagnosed infiltrative and disseminated drug-sensitive and drug-resistant pulmonary tuberculosis. The key stages in receptor-mediated activation of T-lymphocytes, isolated from blood, after their CD3/CD28-induction in vitro with addition of intracellular transport blocker were analyzed. Their immunotyping was carried out with the method of two- and threecolor flow cytofluorometry. The obtained results were statistically analyzed.Results. The breach of extracellular and intracellular stages of T-lymphocytes activation, shown by reduction in total number of CD3- and CD28-positive cells, and CD3+CD28+IL2+, CD3+CD28+IL2–, CD3+NF-kB+, CD3+NFAT2+ lymphocytes, and increase in number of CD3+CTLA4+ cells, was identified with most of their manifestations in disseminated drug-resistant pulmonary tuberculosis. It was shown that the content of CD3+AP-1+ lymphocytes is variable in drug-resistant pulmonary tuberculosis: it increases in the infiltrative form and decreases in the disseminated form.Conclusion. The results showed different mechanisms leading to a deficiency of IL-2-positive lymphocytes and T-lymphocytopenia: from “functional reserve” exhaustion of T-cells in drug-sensitive pulmonary tuberculosis to immunosuppression under the influence of suppressive cytokines (in case of the infiltrative form and inhibitory protein CTLA4 (in case of the disseminated form in drug-resistant pulmonary tuberculosis. 

Isolation of pulmonary artery smooth muscle cells from neonatal mice.

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Lee, Keng Jin; Czech, Lyubov; Waypa, Gregory B; Farrow, Kathryn N

2013-10-19

Pulmonary hypertension is a significant cause of morbidity and mortality in infants. Historically, there has been significant study of the signaling pathways involved in vascular smooth muscle contraction in PASMC from fetal sheep. While sheep make an excellent model of term pulmonary hypertension, they are very expensive and lack the advantage of genetic manipulation found in mice. Conversely, the inability to isolate PASMC from mice was a significant limitation of that system. Here we described the isolation of primary cultures of mouse PASMC from P7, P14, and P21 mice using a variation of the previously described technique of Marshall et al. that was previously used to isolate rat PASMC. These murine PASMC represent a novel tool for the study of signaling pathways in the neonatal period. Briefly, a slurry of 0.5% (w/v) agarose + 0.5% iron particles in M199 media is infused into the pulmonary vascular bed via the right ventricle (RV). The iron particles are 0.2 μM in diameter and cannot pass through the pulmonary capillary bed. Thus, the iron lodges in the small pulmonary arteries (PA). The lungs are inflated with agarose, removed and dissociated. The iron-containing vessels are pulled down with a magnet. After collagenase (80 U/ml) treatment and further dissociation, the vessels are put into a tissue culture dish in M199 media containing 20% fetal bovine serum (FBS), and antibiotics (M199 complete media) to allow cell migration onto the culture dish. This initial plate of cells is a 50-50 mixture of fibroblasts and PASMC. Thus, the pull down procedure is repeated multiple times to achieve a more pure PASMC population and remove any residual iron. Smooth muscle cell identity is confirmed by immunostaining for smooth muscle myosin and desmin.

Acrolein effects in pulmonary cells: relevance to chronic obstructive pulmonary disease.

Science.gov (United States)

Moretto, Nadia; Volpi, Giorgia; Pastore, Fiorella; Facchinetti, Fabrizio

2012-07-01

Acrolein (2-propenal) is a highly reactive α,β-unsaturated aldehyde and a respiratory irritant that is ubiquitously present in the environment but that can also be generated endogenously at sites of inflammation. Acrolein is abundant in tobacco smoke, which is the major environmental risk factor for chronic obstructive pulmonary disease (COPD), and elevated levels of acrolein are found in the lung fluids of COPD patients. Its high electrophilicity makes acrolein notorious for its facile reaction with biological nucleophiles, leading to the modification of proteins and DNA and depletion of antioxidant defenses. As a consequence, acrolein results in oxidative stress as well as altered intracellular signaling and gene transcription/translation. In pulmonary cells, acrolein, at subtoxic concentrations, can activate intracellular stress kinases, alter the production of inflammatory mediators and proteases, modify innate immune response, induce mucus hypersecretion, and damage airway epithelium. A better comprehension of the mechanisms underlying acrolein effects in the airways may suggest novel treatment strategies in COPD. © 2012 New York Academy of Sciences.

Expansion and exfoliation of graphite to form graphene

KAUST Repository

Patole, Shashikan P.

2017-07-27

Graphene production methods are described based on subjecting non- covalent graphite intercalated compounds, such as graphite bisulfate, to expansion conditions such as shocks of heat and/or microwaves followed by turbulence-assisted exfoliation to produce few-layer, high quality graphene flakes. Depending on the approach selected for the exfoliation step, free-flowing graphene powder, graphene slurry, or an aqueous graphene mixture can be obtained. Surfactants can aid in dispersion, and graphene inks can be formed. The parameters of the process are simple, efficient and low-cost enabling therefore the scale- up of production. Applications include electrodes and energy storage devices.

Exfoliation and thermal transformations of Nb-substituted layered titanates

DEFF Research Database (Denmark)

Song, H.; Sjåstad, Anja O.; Fjellvåg, Helmer

2011-01-01

Single-layer Nb-substituted titanate nanosheets of ca. 1 nm thickness were obtained by exfoliating tetrabutylammonium (TBA)-intercalated Nb-substituted titanates in water. AFM images and turbidity measurements reveal that the exfoliated nanosheets crack and corrugate when sonicated. Upon heating...... factors for increasing the transformation temperatures for conversion of the nanosheets to anatase and finally into rutile. It is further tempting to link the delay in crystallization to morphology limitations originating from the nanosheets. The present work shows that layered Nb-titanates...

Assessment of nuclear abnormalities in exfoliated cells from the oral epithelium of mobile phone users.

Science.gov (United States)

Souza, Leonardo da Cunha Menezes; Cerqueira, Eneida de Moraes Marcílio; Meireles, José Roberto Cardoso

2014-06-01

Transmission and reception of mobile telephony signals take place through electromagnetic wave radiation, or electromagnetic radiofrequency fields, between the mobile terminal and the radio base station. Based on reports in the literature on adverse effects from exposure to this type of radiation, the objective of this study was to evaluate the genotoxic and cytotoxic potential of such exposure, by means of the micronucleus test on exfoliated cells from the oral epithelium. The sample included 45 individuals distributed in 3 groups according to the amount of time in hours per week (t) spent using mobile phones: group I, t > 5 h; group II, t > 1 h and ≤ 5 h; and group III, t ≤ 1 h. Cells from the oral mucosa were analyzed to assess the numbers of micronuclei, broken egg structures and degenerative nuclear abnormalities indicative of apoptosis (condensed chromatin, karyorrhexis and pyknosis) or necrosis (karyolysis in addition to these changes). The occurrences of micronuclei and degenerative nuclear abnormalities did not differ between the groups, but the number of broken egg (structures that may be associated with gene amplification) was significantly greater in the individuals in group I (p < 0.05).

Pulmonary squamous cell carcinoma following head and neck squamous cell carcinoma: Metastasis or second primary?

NARCIS (Netherlands)

Geurts, Tom W.; Nederlof, Petra M.; van den Brekel, Michiel W. M.; van't Veer, Laura J.; de Jong, Daphne; Hart, August A. M.; van Zandwijk, Nico; Klomp, Houke; Balm, Alfons J. M.; van Velthuysen, Marie-Louise F.

2005-01-01

Purpose: To distinguish a metastasis from a second primary tumor in patients with a history of head and neck squamous cell carcinoma and subsequent pulmonary squamous cell carcinoma. Experimental Design: For 44 patients with a primary squamous cell carcinoma of the head and neck followed by a

Electrochemical Exfoliation of Graphite in Aqueous Sodium Halide Electrolytes toward Low Oxygen Content Graphene for Energy and Environmental Applications.

Science.gov (United States)

Munuera, J M; Paredes, J I; Enterría, M; Pagán, A; Villar-Rodil, S; Pereira, M F R; Martins, J I; Figueiredo, J L; Cenis, J L; Martínez-Alonso, A; Tascón, J M D

2017-07-19

Graphene and graphene-based materials have shown great promise in many technological applications, but their large-scale production and processing by simple and cost-effective means still constitute significant issues in the path of their widespread implementation. Here, we investigate a straightforward method for the preparation of a ready-to-use and low oxygen content graphene material that is based on electrochemical (anodic) delamination of graphite in aqueous medium with sodium halides as the electrolyte. Contrary to previous conflicting reports on the ability of halide anions to act as efficient exfoliating electrolytes in electrochemical graphene exfoliation, we show that proper choice of both graphite electrode (e.g., graphite foil) and sodium halide concentration readily leads to the generation of large quantities of single-/few-layer graphene nanosheets possessing a degree of oxidation (O/C ratio down to ∼0.06) lower than that typical of anodically exfoliated graphenes obtained with commonly used electrolytes. The halide anions are thought to play a role in mitigating the oxidation of the graphene lattice during exfoliation, which is also discussed and rationalized. The as-exfoliated graphene materials exhibited a three-dimensional morphology that was suitable for their practical use without the need to resort to any kind of postproduction processing. When tested as dye adsorbents, they outperformed many previously reported graphene-based materials (e.g., they adsorbed ∼920 mg g -1 for methyl orange) and were useful sorbents for oils and nonpolar organic solvents. Supercapacitor cells assembled directly from the as-exfoliated products delivered energy and power density values (up to 15.3 Wh kg -1 and 3220 W kg -1 , respectively) competitive with those of many other graphene-based devices but with the additional advantage of extreme simplicity of preparation.

Imidazolium Ionic Liquid Mediates Black Phosphorus Exfoliation while Preventing Phosphorene Decomposition.

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Chaban, Vitaly V; Fileti, Eudes Eterno; Prezhdo, Oleg V

2017-06-27

Forthcoming applications in electronics and optoelectronics make phosphorene a subject of vigorous research efforts. Solvent-assisted exfoliation of phosphorene promises affordable delivery in industrial quantities for future applications. We demonstrate, using equilibrium, steered and umbrella sampling molecular dynamics, that the 1-ethyl-3-methylimidazolium tetrafluoroborate [EMIM][BF 4 ] ionic liquid is an excellent solvent for phosphorene exfoliation. The presence of both hydrophobic and hydrophilic moieties, as well as substantial shear viscosity, allows [EMIM][BF 4 ] simultaneously to facilitate separation of phosphorene sheets and to protect them from getting in direct contact with moisture and oxygen. The exfoliation thermodynamics is moderately unfavorable, which indicates that an external stimulus is necessary. Unexpectedly, [EMIM][BF 4 ] does not coordinates phosphorene by π-electron stacking with the imidazole ring. Instead, the solvation proceeds via hydrophobic side chains, while polar imidazole rings form an electrostatically stabilized protective layer. The simulations suggest that further efforts in solvent engineering for phosphorene exfoliation should concentrate on use of weakly coordinating ions and grafting groups that promote stronger dispersion interactions and on elongation of nonpolar chains.

Tunable UV-visible absorption of SnS2 layered quantum dots produced by liquid phase exfoliation.

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Fu, Xiao; Ilanchezhiyan, P; Mohan Kumar, G; Cho, Hak Dong; Zhang, Lei; Chan, A Sattar; Lee, Dong J; Panin, Gennady N; Kang, Tae Won

2017-02-02

4H-SnS 2 layered crystals synthesized by a hydrothermal method were used to obtain via liquid phase exfoliation quantum dots (QDs), consisting of a single layer (SLQDs) or multiple layers (MLQDs). Systematic downshift of the peaks in the Raman spectra of crystals with a decrease in size was observed. The bandgap of layered QDs, estimated by UV-visible absorption spectroscopy and the tunneling current measurements using graphene probes, increases from 2.25 eV to 3.50 eV with decreasing size. 2-4 nm SLQDs, which are transparent in the visible region, show selective absorption and photosensitivity at wavelengths in the ultraviolet region of the spectrum while larger MLQDs (5-90 nm) exhibit a broad band absorption in the visible spectral region and the photoresponse under white light. The results show that the layered quantum dots obtained by liquid phase exfoliation exhibit well-controlled and regulated bandgap absorption in a wide tunable wavelength range. These novel layered quantum dots prepared using an inexpensive method of exfoliation and deposition from solution onto various substrates at room temperature can be used to create highly efficient visible-blind ultraviolet photodetectors and multiple bandgap solar cells.

Abnormal pulmonary function in adults with sickle cell anemia.

Science.gov (United States)

Klings, Elizabeth S; Wyszynski, Diego F; Nolan, Vikki G; Steinberg, Martin H

2006-06-01

Pulmonary complications of sickle cell anemia (Hb-SS) commonly cause morbidity, yet few large studies of pulmonary function tests (PFTs) in this population have been reported. PFTs (spirometry, lung volumes, and diffusion capacity for carbon monoxide [DLCO]) from 310 adults with Hb-SS were analyzed to determine the pattern of pulmonary dysfunction and their association with other systemic complications of sickle cell disease. Raw PFT data were compared with predicted values. Each subject was subclassified into one of five groups: obstructive physiology, restrictive physiology, mixed obstructive/restrictive physiology, isolated low DLCO, or normal. The association between laboratory data of patients with decreased DLCO or restrictive physiology and those of normal subjects was assessed by multivariate linear regression. Normal PFTs were present in only 31 of 310 (10%) patients. Overall, adults with Hb-SS were characterized by decreased total lung capacities (70.2 +/- 14.7% predicted) and DLCO (64.5 +/- 19.9%). The most common PFT patterns were restrictive physiology (74%) and isolated low DLCO (13%). Decreased DLCO was associated with thrombocytosis (p = 0.05), with hepatic dysfunction (elevated alanine aminotransferase; p = 0.07), and a trend toward renal dysfunction (elevated blood urea nitrogen and creatinine; p = 0.05 and 0.07, respectively). Pulmonary function is abnormal in 90% of adult patients with Hb-SS. Common abnormalities include restrictive physiology and decreased DLCO. Decreased DLCO may indicate more severe sickle vasculopathy characterized by impaired hepatic and renal function.

Regulatory T Cells Promote β-Catenin–Mediated Epithelium-to-Mesenchyme Transition During Radiation-Induced Pulmonary Fibrosis

International Nuclear Information System (INIS)

Xiong, Shanshan; Pan, Xiujie; Xu, Long; Yang, Zhihua; Guo, Renfeng; Gu, Yongqing; Li, Ruoxi; Wang, Qianjun; Xiao, Fengjun; Du, Li; Zhou, Pingkun; Zhu, Maoxiang

2015-01-01

Purpose: Radiation-induced pulmonary fibrosis results from thoracic radiation therapy and severely limits radiation therapy approaches. CD4 + CD25 + FoxP3 + regulatory T cells (Tregs) as well as epithelium-to-mesenchyme transition (EMT) cells are involved in pulmonary fibrosis induced by multiple factors. However, the mechanisms of Tregs and EMT cells in irradiation-induced pulmonary fibrosis remain unclear. In the present study, we investigated the influence of Tregs on EMT in radiation-induced pulmonary fibrosis. Methods and Materials: Mice thoraxes were irradiated (20 Gy), and Tregs were depleted by intraperitoneal injection of a monoclonal anti-CD25 antibody 2 hours after irradiation and every 7 days thereafter. Mice were treated on days 3, 7, and 14 and 1, 3, and 6 months post irradiation. The effectiveness of Treg depletion was assayed via flow cytometry. EMT and β-catenin in lung tissues were detected by immunohistochemistry. Tregs isolated from murine spleens were cultured with mouse lung epithelial (MLE) 12 cells, and short interfering RNA (siRNA) knockdown of β-catenin in MLE 12 cells was used to explore the effects of Tregs on EMT and β-catenin via flow cytometry and Western blotting. Results: Anti-CD25 antibody treatment depleted Tregs efficiently, attenuated the process of radiation-induced pulmonary fibrosis, hindered EMT, and reduced β-catenin accumulation in lung epithelial cells in vivo. The coculture of Tregs with irradiated MLE 12 cells showed that Tregs could promote EMT in MLE 12 cells and that the effect of Tregs on EMT was partially abrogated by β-catenin knockdown in vitro. Conclusions: Tregs can promote EMT in accelerating radiation-induced pulmonary fibrosis. This process is partially mediated through β-catenin. Our study suggests a new mechanism for EMT, promoted by Tregs, that accelerates radiation-induced pulmonary fibrosis

Regulatory T Cells Promote β-Catenin–Mediated Epithelium-to-Mesenchyme Transition During Radiation-Induced Pulmonary Fibrosis

Energy Technology Data Exchange (ETDEWEB)

Xiong, Shanshan; Pan, Xiujie; Xu, Long; Yang, Zhihua [Beijing Institute of Radiation Medicine, Beijing (China); Guo, Renfeng [Department of Pathology, University of Michigan Medical School, Ann Arbor, Michigan (United States); Gu, Yongqing; Li, Ruoxi; Wang, Qianjun; Xiao, Fengjun; Du, Li; Zhou, Pingkun [Beijing Institute of Radiation Medicine, Beijing (China); Zhu, Maoxiang, E-mail: zhumx@nic.bmi.ac.cn [Beijing Institute of Radiation Medicine, Beijing (China)

2015-10-01

Purpose: Radiation-induced pulmonary fibrosis results from thoracic radiation therapy and severely limits radiation therapy approaches. CD4{sup +}CD25{sup +}FoxP3{sup +} regulatory T cells (Tregs) as well as epithelium-to-mesenchyme transition (EMT) cells are involved in pulmonary fibrosis induced by multiple factors. However, the mechanisms of Tregs and EMT cells in irradiation-induced pulmonary fibrosis remain unclear. In the present study, we investigated the influence of Tregs on EMT in radiation-induced pulmonary fibrosis. Methods and Materials: Mice thoraxes were irradiated (20 Gy), and Tregs were depleted by intraperitoneal injection of a monoclonal anti-CD25 antibody 2 hours after irradiation and every 7 days thereafter. Mice were treated on days 3, 7, and 14 and 1, 3, and 6 months post irradiation. The effectiveness of Treg depletion was assayed via flow cytometry. EMT and β-catenin in lung tissues were detected by immunohistochemistry. Tregs isolated from murine spleens were cultured with mouse lung epithelial (MLE) 12 cells, and short interfering RNA (siRNA) knockdown of β-catenin in MLE 12 cells was used to explore the effects of Tregs on EMT and β-catenin via flow cytometry and Western blotting. Results: Anti-CD25 antibody treatment depleted Tregs efficiently, attenuated the process of radiation-induced pulmonary fibrosis, hindered EMT, and reduced β-catenin accumulation in lung epithelial cells in vivo. The coculture of Tregs with irradiated MLE 12 cells showed that Tregs could promote EMT in MLE 12 cells and that the effect of Tregs on EMT was partially abrogated by β-catenin knockdown in vitro. Conclusions: Tregs can promote EMT in accelerating radiation-induced pulmonary fibrosis. This process is partially mediated through β-catenin. Our study suggests a new mechanism for EMT, promoted by Tregs, that accelerates radiation-induced pulmonary fibrosis.

Acetone improves the topographical homogeneity of liquid phase exfoliated few-layer black phosphorus flakes.

Science.gov (United States)

Gomez Perez, Juan; Konya, Zoltan; Kukovecz, Akos

2018-06-12

Liquid phase exfoliation of 2D materials has issues related to the sorption of the solvent, the oxidation of the sample during storage, and the topographical inhomogeneity of the exfoliated material. N-methyl-2-pyrrolidone (NMP), a common solvent for black phosphorus (BP) exfoliation, has additional drawbacks like the formation of by-products during sonication and poor solvent volatility. Here we demonstrate an improvement in the topographical homogeneity (i.e. thickness and lateral dimensions) of NMP-exfoliated BP flakes after resuspension in acetone. The typical size of monolayers and bilayers stabilised in acetone was 99.8±27.4 nm and 159.1±57 nm, respectively. These standard deviations represent a threefold improvement over those of the NMP-exfoliated originals. Phosphorene can also be exfoliated directly in acetone by very long ultrasonication. The product suspension enjoys the same dimensional homogeneity benefits, which confirms that this effect is an intrinsic property of the acetone-BP system. The quality and stability of the exfoliated flakes was checked by XRD, TEM, electron diffraction and Raman spectroscopy. Thermal expansion coefficients of the A1g, B2g and A2g Raman modes were calculated for drop-casted samples as -0.01828 cm-1/K, -0.03056 cm-1/K and -0.03219 cm-1/K, respectively. The flakes withstand 20 minutes in O2 flow at 373 K without lattice distortion. . © 2018 IOP Publishing Ltd.

Pioneers of exfoliative cytology in the 19th century: the predecessors of George Papanicolaou.

Science.gov (United States)

Diamantis, A; Magiorkinis, E

2014-08-01

The purpose of our study was to summarize the knowledge on exfoliative cytology during the 19th century and to track down Papanicolaou's predecessors. A thorough study of texts, medical books and reports, together with a review of the available literature in PubMed, was undertaken. The study of cytological preparations as a diagnostic procedure can be traced back to the work of the famous French microscopist Alfred François Donné. However, the systematic study and the criteria for the diagnosis of malignant cells should be attributed to Johannes Müller. The increasing interest in the cytological examination of various fluids of the human body can be confirmed by a plethora of studies published during this period. By the end of the 19th century, the invention of new techniques in pathology, such as the introduction of cell block techniques, tissue sections and new staining methods which provided the opportunity to study surgical specimens in three dimensions, led to a decrease in the interest in exfoliative cytology, which was re-discovered by George Papanicolaou almost three decades later. © 2013 John Wiley & Sons Ltd.

SPDEF is required for mouse pulmonary goblet cell differentiation and regulates a network of genes associated with mucus production.

Science.gov (United States)

Chen, Gang; Korfhagen, Thomas R; Xu, Yan; Kitzmiller, Joseph; Wert, Susan E; Maeda, Yutaka; Gregorieff, Alexander; Clevers, Hans; Whitsett, Jeffrey A

2009-10-01

Various acute and chronic inflammatory stimuli increase the number and activity of pulmonary mucus-producing goblet cells, and goblet cell hyperplasia and excess mucus production are central to the pathogenesis of chronic pulmonary diseases. However, little is known about the transcriptional programs that regulate goblet cell differentiation. Here, we show that SAM-pointed domain-containing Ets-like factor (SPDEF) controls a transcriptional program critical for pulmonary goblet cell differentiation in mice. Initial cell-lineage-tracing analysis identified nonciliated secretory epithelial cells, known as Clara cells, as the progenitors of goblet cells induced by pulmonary allergen exposure in vivo. Furthermore, in vivo expression of SPDEF in Clara cells caused rapid and reversible goblet cell differentiation in the absence of cell proliferation. This was associated with enhanced expression of genes regulating goblet cell differentiation and protein glycosylation, including forkhead box A3 (Foxa3), anterior gradient 2 (Agr2), and glucosaminyl (N-acetyl) transferase 3, mucin type (Gcnt3). Consistent with these findings, levels of SPDEF and FOXA3 were increased in mouse goblet cells after sensitization with pulmonary allergen, and the proteins were colocalized in goblet cells lining the airways of patients with chronic lung diseases. Deletion of the mouse Spdef gene resulted in the absence of goblet cells in tracheal/laryngeal submucosal glands and in the conducting airway epithelium after pulmonary allergen exposure in vivo. These data show that SPDEF plays a critical role in regulating a transcriptional network mediating the goblet cell differentiation and mucus hyperproduction associated with chronic pulmonary disorders.

Differential induction of micronuclei in peripheral lymphocytes and exfoliated urothelial cells of workers exposed to 4,4'-methylenebis-(2-chloroaniline) (MOCA) and bitumen fumes.

Science.gov (United States)

Murray, E B; Edwards, J W

2005-01-01

Cytogenetic end-points used to estimate risk of genotoxic events in workers include the measurement of micronuclei (MN) in exfoliated cells, lymphocytes, and other tissues. Micronuclei are chromatin-containing bodies outside the cell nucleus resulting from contaminant-induced DNA damage. A review of 71 reports of human genotoxic responses to chemical or physical agents published between 1999 and 2001 revealed that 14% of such studies measured genotoxicity endpoints in specific target tissues relevant to the site of disease for the agent examined; 18% used endpoints in surrogate or non-target tissues but considered the relations between endpoints in surrogate and disease target tissues, and 68% measured genotoxicity endpoints in accessible tissues without reference to specific targets for disease. Methylenebis-(2-chloroaniline) (MOCA), used in polyurethane manufacture, is a suspected bladder carcinogen. Bitumen, used in road surfacing, contains skin and lung carcinogens. In this study, we aimed to compare genotoxicity in urothelial cells and in lymphocytes of workers exposed to these materials. Twelve men employed in polyurethane manufacture, twelve bitumen road layers, and eighteen hospital stores personnel (controls) were recruited and all provided blood and urine samples on the same day. Blood cultures were prepared using a cytochalasin B-block method. Exfoliated urothelial cells were collected from urine and stained for light microscopy. The number of MN in urothelial cells was higher in MOCA-exposed (14.27 +/- 0.56 MN/1000, 9.69 +/- 0.32 MN cells/1000) than in bitumen exposed workers (11.99 +/- 0.65 MN/1000, 8.66 +/- 0.46 MN cells/1000) or in control subjects (6.88 +/- 0.18 MN/1000, 5.17 +/- 0.11 MN cells/1000). Conversely, in lymphocytes, MN were higher in bitumen-exposed (16.24 +/- 0.63 MN/1000, 10.65 +/- 0.24 MN cells/1000) than in MOCA-exposed workers (13.25 +/- 0.48 MN/1000, 8.54 +/- 0.14 MN cells/1000) or in control subjects (9.24 +/- 0.29 MN/ 1000, 5

Increased CYP1A1 expression in human exfoliated urothelial cells of cigarette smokers compared to non-smokers

Energy Technology Data Exchange (ETDEWEB)

Doerrenhaus, Angelika; Roos, Peter H. [Institute for Occupational Physiology at the University Dortmund, Dortmund (Germany); Mueller, Tina [Institute for Occupational Physiology at the University Dortmund, Dortmund (Germany); University Dortmund, Department of Statistics, Mathematical Statistics with Applications in Biometrics, Dortmund (Germany)

2007-01-15

Polycyclic aromatic hydrocarbons, arylamines and nitrosamines, constituents of cigarette smoke, are known inducers of bladder cancer. The biochemical response of the target tissue, the bladder urothelium, following inhalation of cigarette smoke has not been studied so far. We used exfoliated transitional urothelial cells from human urine samples to analyze effects of smoking on induction of the cytochrome P450 enzyme CYP1A1. Samples of 40 subjects, including male and female smokers and non-smokers, were examined. A prerequisite for the immunofluorescence microscopic analysis of the cells was the enrichment of the urothelial cell population. This was achieved by a new method which is based on magnetic cell sorting exploiting specific binding of immobilized Griffonia simplicifolia lectin to the surface of urothelial cells. Immunostaining of the final cell preparation with a monoclonal antibody to CYP1A1 showed that about 6% of the urothelial cells of non-smokers stained positive for CYP1A1. However, this fraction of positive cells was more than 44% of the urothelial cells in samples from cigarette smokers. In spite of the individual variation, the difference was statistically significant. There were no gender-related differences in the portion of CYP1A1 expressing urothelial cells of smokers and non-smokers. In essence, we show for the first time that human urothelial cells respond to cigarette smoking by induction of CYP1A1. The approach opens new fields of mechanistic and biomarker research with respect to the pathogenetic processes of cancer development in the human bladder. (orig.)

Rapid Fatal Outcome from Pulmonary Arteries Compression in Transitional Cell Carcinoma

Directory of Open Access Journals (Sweden)

Ioannis A. Voutsadakis

2009-01-01

Full Text Available Transitional cell carcinoma of the urinary bladder is a malignancy that metastasizes frequently to lymph nodes including the mediastinal lymph nodes. This occurrence may produce symptoms due to compression of adjacent structures such as the superior vena cava syndrome or dysphagia from esophageal compression. We report the case of a 59-year-old man with metastatic transitional cell carcinoma for whom mediastinal lymphadenopathy led to pulmonary artery compression and a rapidly fatal outcome. This rare occurrence has to be distinguished from pulmonary embolism, a much more frequent event in cancer patients, in order that proper and prompt treatment be initiated.

Reliable Exfoliation of Large-Area High-Quality Flakes of Graphene and Other Two-Dimensional Materials.

Science.gov (United States)

Huang, Yuan; Sutter, Eli; Shi, Norman N; Zheng, Jiabao; Yang, Tianzhong; Englund, Dirk; Gao, Hong-Jun; Sutter, Peter

2015-11-24

Mechanical exfoliation has been a key enabler of the exploration of the properties of two-dimensional materials, such as graphene, by providing routine access to high-quality material. The original exfoliation method, which remained largely unchanged during the past decade, provides relatively small flakes with moderate yield. Here, we report a modified approach for exfoliating thin monolayer and few-layer flakes from layered crystals. Our method introduces two process steps that enhance and homogenize the adhesion force between the outermost sheet in contact with a substrate: Prior to exfoliation, ambient adsorbates are effectively removed from the substrate by oxygen plasma cleaning, and an additional heat treatment maximizes the uniform contact area at the interface between the source crystal and the substrate. For graphene exfoliation, these simple process steps increased the yield and the area of the transferred flakes by more than 50 times compared to the established exfoliation methods. Raman and AFM characterization shows that the graphene flakes are of similar high quality as those obtained in previous reports. Graphene field-effect devices were fabricated and measured with back-gating and solution top-gating, yielding mobilities of ∼4000 and 12,000 cm(2)/(V s), respectively, and thus demonstrating excellent electrical properties. Experiments with other layered crystals, e.g., a bismuth strontium calcium copper oxide (BSCCO) superconductor, show enhancements in exfoliation yield and flake area similar to those for graphene, suggesting that our modified exfoliation method provides an effective way for producing large area, high-quality flakes of a wide range of 2D materials.

WS_2 nanosheets based on liquid exfoliation as effective electrocatalysts for hydrogen evolution reaction

International Nuclear Information System (INIS)

Han, Guan-Qun; Liu, Yan-Ru; Hu, Wen-Hui; Dong, Bin; Li, Xiao; Chai, Yong-Ming; Liu, Yun-Qi; Liu, Chen-Guang

2015-01-01

WS_2 nanosheets (WS_2 NSs) as electrocatalysts for hydrogen evolution reaction (HER) have been prepared based on liquid exfoliation in dimethyl-formamide (DMF) via a direct dispersion and ultrasonication method. X-ray diffraction (XRD) shows the decreasing crystalline of the exfoliated WS_2 (E-WS_2). Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) show that the as prepared E-WS_2 consists of a few two-dimensional nanosheets, with large wrinkles on the surface. Electrochemical measurements show an excellent activity and stability of the E-WS_2, with a low overpotential of 80 mV and high current density (10 mA cm"−"2, at η = 205 mV), which indicates that through the process of exfoliation in DMF, both the dispersion and the amount of active sites have been improved greatly. Therefore, DMF is a promising alternative for exfoliating two-dimensional nanomaterials for highly efficient HER electrocatalysts. - Highlights: • A facile exfoliation process in DMF has been used to prepare E-WS_2 for HER. • E-WS_2 shows the better electrocatalytic activity than bulk WS_2. • DMF provides a promising alternative for enhancing exfoliation of 2D materials.

Identification of genuine primary pulmonary NK cell lymphoma via clinicopathologic observation and clonality assay.

Science.gov (United States)

Gong, Li; Wei, Long-Xiao; Huang, Gao-Sheng; Zhang, Wen-Dong; Wang, Lu; Zhu, Shao-Jun; Han, Xiu-Juan; Yao, Li; Lan, Miao; Li, Yan-Hong; Zhang, Wei

2013-08-19

Extranodal natural killer (NK)/T-cell lymphoma, nasal type, is an uncommon lymphoma associated with the Epstein-Barr virus (EBV). It most commonly involves the nasal cavity and upper respiratory tract. Primary pulmonary NK/T cell lymphoma is extremely rare. If a patient with a NK or T-cell tumor has an unusual reaction to treatment or an unusual prognosis, it is wise to differentiate NK from T-cell tumors. The clinicopathologic characteristics, immunophenotype, EBV in situ hybridization, and T cell receptor (TCR) gene rearrangement of primary pulmonary NK cell lymphoma from a 73-year-old Chinese woman were investigated and the clonal status was determined using female X-chromosomal inactivation mosaicism and polymorphisms at the phosphoglycerate kinase (PGK) gene. The lesion showed the typical histopathologic characteristics and immunohistochemical features of NK/T cell lymphoma. However, the sample was negative for TCR gene rearrangement. A clonality assay demonstrated that the lesion was monoclonal. It is concluded that this is the first recorded case of genuine primary pulmonary NK cell lymphoma. The purpose of the present work is to recommend that pathologists carefully investigate the whole lesion to reduce the likelihood that primary pulmonary NK cell lymphoma will be misdiagnosed as an infectious lesion. In addition, TCR gene rearrangement and clonal analysis, which is based on female X-chromosomal inactivation mosaicism and polymorphisms at PGK and androgen receptor (AR) loci, were found to play important roles in differentiating NK cell lymphoma from T cell lymphoma. The virtual slide(s) for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/vs/5205300349457729.

Cardio–Pulmonary Response Of Patients With Sickle Cell Anaemia ...

African Journals Online (AJOL)

Cardio–Pulmonary Response Of Patients With Sickle Cell Anaemia ... any risk of adverse cardio-respiratory response during the course of physical rehabilitation. A total of 70 subjects participated in the study; 30 of these had Haemoglobin ...

Mobilization of dust and exfoliation of erosion product films in tokamaks

International Nuclear Information System (INIS)

Martynenko, Yu. V.; Nagel, M. Yu.

2012-01-01

The mobilization of dust (i.e., detachment and removal of dust grains from a substrate) and the exfoliation of a film of erosion products in tokamaks have been studied theoretically. The following mechanisms of dust mobilization have been taken into account: (i) sharp heating (thermal shock) as a result of, e.g., plasma disruption and edge instabilities; (ii) substrate vibrations; and (iii) gas and plasma flow (wind) action. The most effective mobilization takes place under the action of sharp heating. Power fluxes that are characteristic of edge instabilities can mobilize dust grains with dimensions within or even greater than 0.1–1 μm. The velocities of detached grains reach ν ∼ 100 m/s for heavy grains and up to ν ∼ 300 m/s for the light ones. Conditions favoring the exfoliation of a film of erosion products are determined. It is shown that exfoliation under the action of edge instabilities can take place at a film thickness of h > 1 μm. Under the action of thermal-shock-induced stresses, the exfoliated film flakes with a size ranging from fractions of a millimeter to several centimeters break into pieces.

Mobilization of dust and exfoliation of erosion product films in tokamaks

Energy Technology Data Exchange (ETDEWEB)

Martynenko, Yu. V.; Nagel, M. Yu. [National Research Centre Kurchatov Institute (Russian Federation)

2012-04-15

The mobilization of dust (i.e., detachment and removal of dust grains from a substrate) and the exfoliation of a film of erosion products in tokamaks have been studied theoretically. The following mechanisms of dust mobilization have been taken into account: (i) sharp heating (thermal shock) as a result of, e.g., plasma disruption and edge instabilities; (ii) substrate vibrations; and (iii) gas and plasma flow (wind) action. The most effective mobilization takes place under the action of sharp heating. Power fluxes that are characteristic of edge instabilities can mobilize dust grains with dimensions within or even greater than 0.1-1 {mu}m. The velocities of detached grains reach {nu} {approx} 100 m/s for heavy grains and up to {nu} {approx} 300 m/s for the light ones. Conditions favoring the exfoliation of a film of erosion products are determined. It is shown that exfoliation under the action of edge instabilities can take place at a film thickness of h > 1 {mu}m. Under the action of thermal-shock-induced stresses, the exfoliated film flakes with a size ranging from fractions of a millimeter to several centimeters break into pieces.

Abnormal Pulmonary Function in Adults with Sickle Cell Anemia

Science.gov (United States)

Klings, Elizabeth S.; Wyszynski, Diego F.; Nolan, Vikki G.; Steinberg, Martin H.

2006-01-01

Rationale: Pulmonary complications of sickle cell anemia (Hb-SS) commonly cause morbidity, yet few large studies of pulmonary function tests (PFTs) in this population have been reported. Objectives: PFTs (spirometry, lung volumes, and diffusion capacity for carbon monoxide [DLCO]) from 310 adults with Hb-SS were analyzed to determine the pattern of pulmonary dysfunction and their association with other systemic complications of sickle cell disease. Methods: Raw PFT data were compared with predicted values. Each subject was subclassified into one of five groups: obstructive physiology, restrictive physiology, mixed obstructive/restrictive physiology, isolated low DLCO, or normal. The association between laboratory data of patients with decreased DLCO or restrictive physiology and those of normal subjects was assessed by multivariate linear regression. Measurements and Main Results: Normal PFTs were present in only 31 of 310 (10%) patients. Overall, adults with Hb-SS were characterized by decreased total lung capacities (70.2 ± 14.7% predicted) and DlCO (64.5 ± 19.9%). The most common PFT patterns were restrictive physiology (74%) and isolated low DlCO (13%). Decreased DLCO was associated with thrombocytosis (p = 0.05), with hepatic dysfunction (elevated alanine aminotransferase; p = 0.07), and a trend toward renal dysfunction (elevated blood urea nitrogen and creatinine; p = 0.05 and 0.07, respectively). Conclusions: Pulmonary function is abnormal in 90% of adult patients with Hb-SS. Common abnormalities include restrictive physiology and decreased DLCO. Decreased DLCO may indicate more severe sickle vasculopathy characterized by impaired hepatic and renal function. PMID:16556694

Intercalation and Exfoliation of Kaolinite with Sodium Dodecyl Sulfate

Directory of Open Access Journals (Sweden)

Xiaochao Zuo

2018-03-01

Full Text Available Kaolinite (Kaol was intercalated with dimethyl sulfoxide (DMSO and subsequently methanol (MeOH to prepare intercalation compounds Kaol-DMSO and Kaol-MeOH. Kaol-MeOH was used as an intermediate to synthesize Kaol-sodium dodecyl sulfate (SDS intercalation compound (Kaol-SDS via displacement reaction. The ultrasonic exfoliation of Kaol-SDS produced a resultant Kaol-SDS-U. The samples were characterized by X-ray diffraction (XRD, Fourier transformation infrared spectroscopy (FTIR, thermal analysis, scanning electronic microscopy (SEM, transmission electron microscopy (TEM and particle size analysis. The results revealed that the intercalation of sodium dodecyl sulfate into kaolinite layers caused an obvious increase of the basal spacing from 0.72–4.21 nm. The dehydroxylation temperature of Kaol-SDS was obviously lower than that of original kaolinite. During the intercalation process of sodium dodecyl sulfate, a few kaolinite layers were exfoliated and curled up from the edges of the kaolinite sheets. After sonication treatment, the kaolinite layers were further transformed into nanoscrolls, and the exfoliated resultant Kaol-SDS-U possessed a smaller particle size close to nanoscale.

Two-dimensional materials from high-throughput computational exfoliation of experimentally known compounds

Science.gov (United States)

Mounet, Nicolas; Gibertini, Marco; Schwaller, Philippe; Campi, Davide; Merkys, Andrius; Marrazzo, Antimo; Sohier, Thibault; Castelli, Ivano Eligio; Cepellotti, Andrea; Pizzi, Giovanni; Marzari, Nicola

2018-02-01

Two-dimensional (2D) materials have emerged as promising candidates for next-generation electronic and optoelectronic applications. Yet, only a few dozen 2D materials have been successfully synthesized or exfoliated. Here, we search for 2D materials that can be easily exfoliated from their parent compounds. Starting from 108,423 unique, experimentally known 3D compounds, we identify a subset of 5,619 compounds that appear layered according to robust geometric and bonding criteria. High-throughput calculations using van der Waals density functional theory, validated against experimental structural data and calculated random phase approximation binding energies, further allowed the identification of 1,825 compounds that are either easily or potentially exfoliable. In particular, the subset of 1,036 easily exfoliable cases provides novel structural prototypes and simple ternary compounds as well as a large portfolio of materials to search from for optimal properties. For a subset of 258 compounds, we explore vibrational, electronic, magnetic and topological properties, identifying 56 ferromagnetic and antiferromagnetic systems, including half-metals and half-semiconductors.

Controlling the number of graphene sheets exfoliated from graphite by designed normal loading and frictional motion

International Nuclear Information System (INIS)

Lee, Seungjun; Lu, Wei

2014-01-01

We use molecular dynamics to study the exfoliation of patterned nanometer-sized graphite under various normal loading conditions for friction-induced exfoliation. Using highly ordered pyrolytic graphite (HOPG) as well as both amorphous and crystalline SiO 2 substrate as example systems, we show that the exfoliation process is attributed to the corrugation of the HOPG surface and the atomistic roughness of the substrate when they contact under normal loading. The critical normal strain, at which the exfoliation occurs, is higher on a crystalline substrate than on an amorphous substrate. This effect is related to the atomistic flatness and stiffness of the crystalline surface. We observe that an increase of the van der Waals interaction between the graphite and the substrate results in a decrease of the critical normal strain for exfoliation. We find that the magnitude of the normal strain can effectively control the number of exfoliated graphene layers. This mechanism suggests a promising approach of applying designed normal loading while sliding to pattern controlled number of graphene layers or other two-dimensional materials on a substrate surface.

Epoxy based nanocomposites with fully exfoliated unmodified clay: mechanical and thermal properties.

Science.gov (United States)

Li, Binghai; Zhang, Xiaohong; Gao, Jianming; Song, Zhihai; Qi, Guicun; Liu, Yiqun; Qiao, Jinliang

2010-09-01

The unmodified clay has been fully exfoliated in epoxy resin with the aid of a novel ultrafine full-vulcanized powdered rubber. Epoxy/rubber/clay nanocomposites with exfoliated morphology have been successfully prepared. The microstructures of the nanocomposites were characterized by means of X-ray diffraction and transmission electron microscopy. It was found that the unmodified clay was fully exfoliated and uniformly dispersed in the resulting nanocomposite. Characterizations of mechanical properties revealed that the impact strength of this special epoxy/rubber/clay nanocomposite increased up 107% over the neat epoxy resin. Thermal analyses showed that thermal stability of the nanocomposite was much better than that of epoxy nanocomposite based on organically modified clay.

Standard guide for conducting exfoliation corrosion tests in aluminum alloys

CERN Document Server

American Society for Testing and Materials. Philadelphia

1992-01-01

1.1 This guide differs from the usual ASTM standard in that it does not address a specific test. Rather, it is an introductory guide for new users of other standard exfoliation test methods, (see Terminology G 15 for definition of exfoliation). 1.2 This guide covers aspects of specimen preparation, exposure, inspection, and evaluation for conducting exfoliation tests on aluminum alloys in both laboratory accelerated environments and in natural, outdoor atmospheres. The intent is to clarify any gaps in existent test methods. 1.3 The values stated in SI units are to be regarded as the standard. The inch-pound units given in parentheses are for information only. 1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

Pituitary and pulmonary abnormalities in an adult patient with Langerhans cell histiocytosis

International Nuclear Information System (INIS)

Perez, Adrian; Castro, Ricardo; Pantuso, Silvina

2003-01-01

Pulmonary histiocytosis is an uncommon interstitial lung disease, which is infrequent in adults and is part of a spectrum of disorders characterized by monoclonal proliferation and infiltration of organs by Langerhans cells. Histiocytosis X affects only the lungs in more than 85% of the cases. We report a case of a 21-years-old male patient with Diabetes Insipidus (DI) and respiratory symptoms due to a spontaneous pneumothorax with favorable clinical evolution. High-resolution CT demonstrated bilateral nodular and cystic pulmonary lesions. MRI revealed a nodular widening of the pituitary stalk. An endoscopic trans bronchial biopsy was negative for Langerhans cells. After thoracoscopy with surgical biopsy of the lung the diagnosis of Langerhans' cell histiocytosis was confirmed. (author)

Hypoxia-induced mitogenic factor (HIMF/FIZZ1/RELM alpha recruits bone marrow-derived cells to the murine pulmonary vasculature.

Directory of Open Access Journals (Sweden)

Daniel J Angelini

2010-06-01

Full Text Available Pulmonary hypertension (PH is a disease of multiple etiologies with several common pathological features, including inflammation and pulmonary vascular remodeling. Recent evidence has suggested a potential role for the recruitment of bone marrow-derived (BMD progenitor cells to this remodeling process. We recently demonstrated that hypoxia-induced mitogenic factor (HIMF/FIZZ1/RELM alpha is chemotactic to murine bone marrow cells in vitro and involved in pulmonary vascular remodeling in vivo.We used a mouse bone marrow transplant model in which lethally irradiated mice were rescued with bone marrow transplanted from green fluorescent protein (GFP(+ transgenic mice to determine the role of HIMF in recruiting BMD cells to the lung vasculature during PH development. Exposure to chronic hypoxia and pulmonary gene transfer of HIMF were used to induce PH. Both models resulted in markedly increased numbers of BMD cells in and around the pulmonary vasculature; in several neomuscularized small (approximately 20 microm capillary-like vessels, an entirely new medial wall was made up of these cells. We found these GFP(+ BMD cells to be positive for stem cell antigen-1 and c-kit, but negative for CD31 and CD34. Several of the GFP(+ cells that localized to the pulmonary vasculature were alpha-smooth muscle actin(+ and localized to the media layer of the vessels. This finding suggests that these cells are of mesenchymal origin and differentiate toward myofibroblast and vascular smooth muscle. Structural location in the media of small vessels suggests a functional role in the lung vasculature. To examine a potential mechanism for HIMF-dependent recruitment of mesenchymal stem cells to the pulmonary vasculature, we performed a cell migration assay using cultured human mesenchymal stem cells (HMSCs. The addition of recombinant HIMF induced migration of HMSCs in a phosphoinosotide-3-kinase-dependent manner.These results demonstrate HIMF-dependent recruitment of BMD

WS{sub 2} nanosheets based on liquid exfoliation as effective electrocatalysts for hydrogen evolution reaction

Energy Technology Data Exchange (ETDEWEB)

Han, Guan-Qun [State Key Laboratory of Heavy Oil Processing, China University of Petroleum (East China), Qingdao 266580 (China); College of Science, China University of Petroleum (East China), Qingdao 266580 (China); Liu, Yan-Ru; Hu, Wen-Hui [State Key Laboratory of Heavy Oil Processing, China University of Petroleum (East China), Qingdao 266580 (China); Dong, Bin, E-mail: dongbin@upc.edu.cn [State Key Laboratory of Heavy Oil Processing, China University of Petroleum (East China), Qingdao 266580 (China); College of Science, China University of Petroleum (East China), Qingdao 266580 (China); Li, Xiao; Chai, Yong-Ming; Liu, Yun-Qi [State Key Laboratory of Heavy Oil Processing, China University of Petroleum (East China), Qingdao 266580 (China); Liu, Chen-Guang, E-mail: cgliu@upc.edu.cn [State Key Laboratory of Heavy Oil Processing, China University of Petroleum (East China), Qingdao 266580 (China)

2015-11-01

WS{sub 2} nanosheets (WS{sub 2} NSs) as electrocatalysts for hydrogen evolution reaction (HER) have been prepared based on liquid exfoliation in dimethyl-formamide (DMF) via a direct dispersion and ultrasonication method. X-ray diffraction (XRD) shows the decreasing crystalline of the exfoliated WS{sub 2} (E-WS{sub 2}). Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) show that the as prepared E-WS{sub 2} consists of a few two-dimensional nanosheets, with large wrinkles on the surface. Electrochemical measurements show an excellent activity and stability of the E-WS{sub 2}, with a low overpotential of 80 mV and high current density (10 mA cm{sup −2}, at η = 205 mV), which indicates that through the process of exfoliation in DMF, both the dispersion and the amount of active sites have been improved greatly. Therefore, DMF is a promising alternative for exfoliating two-dimensional nanomaterials for highly efficient HER electrocatalysts. - Highlights: • A facile exfoliation process in DMF has been used to prepare E-WS{sub 2} for HER. • E-WS{sub 2} shows the better electrocatalytic activity than bulk WS{sub 2}. • DMF provides a promising alternative for enhancing exfoliation of 2D materials.

Tire containing thermally exfoliated graphite oxide

Science.gov (United States)

Prud'homme, Robert K. (Inventor); Aksay, Ilhan A. (Inventor)

2011-01-01

A tire, tire lining or inner tube, containing a polymer composite, made of at least one rubber and/or at least one elastomer and a modified graphite oxide material, which is a thermally exfoliated graphite oxide with a surface area of from about 300 sq m/g to 2600 sq m/g.

Need for a cooperative study: Pulmonary Langerhans cell histiocytosis and its management in adults

NARCIS (Netherlands)

McClain, Kenneth L.; Gonzalez, Jorge Mario; Jonkers, Rene; de Juli, Emanuela; Egeler, Maarten

2002-01-01

BACKGROUND: Pulmonary involvement with Langerhans cell histiocytosis (LCH, formerly known as histiocytosis-X) presents as an interstitial process in children and adults either with or without symptoms. In contrast to other manifestations of LCH, most patients with pulmonary disease are adults.

Structure, temperature and frequency dependent electrical conductivity of oxidized and reduced electrochemically exfoliated graphite

Science.gov (United States)

Radoń, Adrian; Włodarczyk, Patryk; Łukowiec, Dariusz

2018-05-01

The article presents the influence of reduction by hydrogen in statu nascendi and modification by hydrogen peroxide on the structure and electrical conductivity of electrochemically exfoliated graphite. It was confirmed that the electrochemical exfoliation can be used to produce oxidized nanographite with an average number of 25 graphene layers. The modified electrochemical exfoliated graphite and reduced electrochemical exfoliated graphite were characterized by high thermal stability, what was associated with removing of labile oxygen-containing groups. The presence of oxygen-containing groups was confirmed using Fourier-transform infrared spectroscopy. Influence of chemical modification by hydrogen and hydrogen peroxide on the electrical conductivity was determined in wide frequency (0.1 Hz-10 kHz) and temperature range (-50 °C-100 °C). Material modified by hydrogen peroxide (0.29 mS/cm at 0 °C) had the lowest electrical conductivity. This can be associated with oxidation of unstable functional groups and was also confirmed by analysis of Raman spectra. The removal of oxygen-containing functional groups by hydrogen in statu nascendi resulted in a 1000-fold increase in the electrical conductivity compared to the electrochemical exfoliated graphite.

Osteogenic differentiation of stem cells from human exfoliated deciduous teeth on poly(ε-caprolactone) nanofibers containing strontium phosphate

Energy Technology Data Exchange (ETDEWEB)

Su, Wen-Ta, E-mail: f10549@ntut.edu.tw [Department of Chemical Engineering and Biotechnology, National Taipei University of Technology, Taipei, Taiwan (China); Wu, Pai-Shuen [Department of Chemical Engineering and Biotechnology, National Taipei University of Technology, Taipei, Taiwan (China); Huang, Te-Yang [Department of Orthopedic Surgery, Mackay Memorial Hospital, Taipei, Taiwan (China)

2015-01-01

Mimicking the architecture of the extracellular matrix is an effective strategy for tissue engineering. Composite nanofibers similar to natural bone structure can be prepared via an electrospinning technique and used in biomedical applications. Stem cells from human exfoliated deciduous teeth (SHEDs) can differentiate into multiple cell lineages, such as cells that are alternative sources of stem cells for tissue engineering. Strontium has important functions in bone remodeling; for example, this element can simulate bone formation and decrease bone resorption. Incorporating strontium phosphate into nanofibers provides a potential material for bone tissue engineering. This study investigated the potential of poly(ε-caprolactone) (PCL) nanofibers coated or blended with strontium phosphate for the osteogenic differentiation of SHEDs. Cellular morphology and MTT assay revealed that nanofibers effectively support cellular attachment, spreading, and proliferation. Strontium-loaded PCL nanofibers exhibited higher expressions of collagen type I, alkaline phosphatase, biomineralization, and bone-related genes than pure PCL nanofibers during the osteogenic differentiation of SHEDs. This study demonstrated that strontium can be an effective inducer of osteogenesis for SHEDs. Understanding the function of bioceramics (such as strontium) is useful in designing and developing strategies for bone tissue engineering. - Highlights: • SHEDs have been considered as alternative sources of adult stem cells in tissue engineering. • Strontium phosphate into nanofibers provides a potential material for bone tissue engineering. • Nanofibers coated or blended with strontium phosphate for the osteogenic differentiation of SHEDs.

Osteogenic differentiation of stem cells from human exfoliated deciduous teeth on poly(ε-caprolactone) nanofibers containing strontium phosphate

International Nuclear Information System (INIS)

Su, Wen-Ta; Wu, Pai-Shuen; Huang, Te-Yang

2015-01-01

Mimicking the architecture of the extracellular matrix is an effective strategy for tissue engineering. Composite nanofibers similar to natural bone structure can be prepared via an electrospinning technique and used in biomedical applications. Stem cells from human exfoliated deciduous teeth (SHEDs) can differentiate into multiple cell lineages, such as cells that are alternative sources of stem cells for tissue engineering. Strontium has important functions in bone remodeling; for example, this element can simulate bone formation and decrease bone resorption. Incorporating strontium phosphate into nanofibers provides a potential material for bone tissue engineering. This study investigated the potential of poly(ε-caprolactone) (PCL) nanofibers coated or blended with strontium phosphate for the osteogenic differentiation of SHEDs. Cellular morphology and MTT assay revealed that nanofibers effectively support cellular attachment, spreading, and proliferation. Strontium-loaded PCL nanofibers exhibited higher expressions of collagen type I, alkaline phosphatase, biomineralization, and bone-related genes than pure PCL nanofibers during the osteogenic differentiation of SHEDs. This study demonstrated that strontium can be an effective inducer of osteogenesis for SHEDs. Understanding the function of bioceramics (such as strontium) is useful in designing and developing strategies for bone tissue engineering. - Highlights: • SHEDs have been considered as alternative sources of adult stem cells in tissue engineering. • Strontium phosphate into nanofibers provides a potential material for bone tissue engineering. • Nanofibers coated or blended with strontium phosphate for the osteogenic differentiation of SHEDs

Friction anisotropy-driven domain imaging on exfoliated monolayer graphene.

Science.gov (United States)

Choi, Jin Sik; Kim, Jin-Soo; Byun, Ik-Su; Lee, Duk Hyun; Lee, Mi Jung; Park, Bae Ho; Lee, Changgu; Yoon, Duhee; Cheong, Hyeonsik; Lee, Ki Ho; Son, Young-Woo; Park, Jeong Young; Salmeron, Miquel

2011-07-29

Graphene produced by exfoliation has not been able to provide an ideal graphene with performance comparable to that predicted by theory, and structural and/or electronic defects have been proposed as one cause of reduced performance. We report the observation of domains on exfoliated monolayer graphene that differ by their friction characteristics, as measured by friction force microscopy. Angle-dependent scanning revealed friction anisotropy with a periodicity of 180° on each friction domain. The friction anisotropy decreased as the applied load increased. We propose that the domains arise from ripple distortions that give rise to anisotropic friction in each domain as a result of the anisotropic puckering of the graphene.

Method of producing exfoliated graphite composite compositions for fuel cell flow field plates

Energy Technology Data Exchange (ETDEWEB)

Zhamu, Aruna; Shi, Jinjun; Guo, Jiusheng; Jang, Bor Z

2014-04-08

A method of producing an electrically conductive composite composition, which is particularly useful for fuel cell bipolar plate applications. The method comprises: (a) providing a supply of expandable graphite powder; (b) providing a supply of a non-expandable powder component comprising a binder or matrix material; (c) blending the expandable graphite with the non-expandable powder component to form a powder mixture wherein the non-expandable powder component is in the amount of between 3% and 60% by weight based on the total weight of the powder mixture; (d) exposing the powder mixture to a temperature sufficient for exfoliating the expandable graphite to obtain a compressible mixture comprising expanded graphite worms and the non-expandable component; (e) compressing the compressible mixture at a pressure within the range of from about 5 psi to about 50,000 psi in predetermined directions into predetermined forms of cohered graphite composite compact; and (f) treating the so-formed cohered graphite composite to activate the binder or matrix material thereby promoting adhesion within the compact to produce the desired composite composition. Preferably, the non-expandable powder component further comprises an isotropy-promoting agent such as non-expandable graphite particles. Further preferably, step (e) comprises compressing the mixture in at least two directions. The method leads to composite plates with exceptionally high thickness-direction electrical conductivity.

Orofacial pain and headaches associated with exfoliation glaucoma.

Science.gov (United States)

Noma, Noboru; Iwasa, Mayumi; Young, Andrew; Ikeda, Mariko; Hsu, Yung-Chu; Yamamoto, Maasa; Inoue, Kenji; Imamura, Yoshiki

2017-12-01

Exfoliation syndrome is the most common identifiable cause of open-angle glaucoma. The authors report a case of exfoliation glaucoma in a patient who had orofacial pain. A 77-year-old woman was treated at the orofacial pain clinic for left-sided facial pain and headaches of 7 months' duration. Her cataracts and open-angle glaucoma had been diagnosed approximately 3 years earlier. Her main symptoms were orofacial pain, eye redness, inflammation of the eyelids, and eyelid edema. Magnetic resonance imaging showed no evidence of intracranial or extracranial pathology. Hemicrania continua was considered as a possible diagnosis. Indomethacin was prescribed but did not affect her headaches. She then went to an ophthalmologist to rule out secondary headaches. Intraocular pressure was 13 millimeters of mercury in the right eye and 67 mm Hg in the left eye. The ophthalmologist made a diagnosis of exfoliation glaucoma, and the patient underwent surgical treatment for the glaucoma and cataracts. After surgery, she was free of symptoms, and intraocular pressure was 15 mm Hg in the left eye. During differential diagnosis, dentists need to consider intraoral and systemic conditions that can mimic odontogenic or orofacial pain disorders in the patient's medical history and that have a higher incidence associated with the patient's age. Copyright © 2017 American Dental Association. Published by Elsevier Inc. All rights reserved.

Large-scale exfoliation of inorganic layered compounds in aqueous surfactant solutions

Energy Technology Data Exchange (ETDEWEB)

Smith, Ronan J.; King, Paul J.; Lotya, Mustafa; Wirtz, Christian; Khan, Umar; De, Sukanta; O' Neill, Arlene; Coleman, Jonathan N. [School of Physics, Trinity College Dublin, Dublin 2 (Ireland); CRANN, Trinity College Dublin, Dublin 2 (Ireland); Duesberg, Georg S. [CRANN, Trinity College Dublin, Dublin 2 (Ireland); School of Chemistry, Trinity College Dublin, Dublin 2 (Ireland); Grunlan, Jaime C.; Moriarty, Gregory [Department of Mechanical Engineering, Texas A and M University, College Station, Texas 77843 (United States); Chen, Jun [Intelligent Polymer Research Institute, ARC Centre of Excellence for Electromaterials Science, AIIM Facility, University of Wollongong, NSW 2522 (Australia); Wang, Jiazhao [Institute for Superconducting and Electronic Materials, ARC Centre of Excellence for Electromaterials Science, University of Wollongong, NSW 2522 (Australia); Minett, Andrew I. [Laboratory for Sustainable Technology, School of Chemical and Biomolecular Engineering, University of Sydney, Sydney, NSW 2006 (Australia); Nicolosi, Valeria [Department of Materials, University of Oxford, Parks Road, Oxford OX1 3PH (United Kingdom)

2011-09-08

A method to exfoliate MoS{sub 2} in large quantities in surfactant-water solutions is described. The layered material tends to be exfoliated as dispersions of thin, relatively defect-free flakes with lateral sizes of hundreds of nanometers. This method can be extended to a range of other layered compounds. The dispersed flakes can be mixed with nanotubes or graphene to greate functional hybrid materials. (Copyright copyright 2011 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

Nuclear anomalies in exfoliated buccal epithelial cells of petrol station attendants in Udaipur, Rajasthan

Directory of Open Access Journals (Sweden)

Rashmi Metgud

2015-01-01

Full Text Available Aim: The petroleum derivatives consist of a complex mixture of chemical compounds one among which is benzene. Petrol station workers who pump fuel to vehicles absorb the products of fuel fumes and the products of combustion. Materials and Methods: To study the occupational exposure to petroleum derivatives such as benzene, exfoliated buccal cells from 40 petrol station attendants and 40 age-matched control subjects were examined for micronuclei, binucleation, karyorrhexis and karyolysis frequency by using feulgen and Giemsa stains. Statistical evaluation was performed with ANOVA test. Results: In the present study, inter-comparison of mean values for micronuclei, binucleation, karyorrhexis and karyolysis using Fuelgen stain between smokers of study and control group, as well as between smokers and non-smokers of study and control group revealed statistically highly significant results with P value 0.00002 and 0.0001 respectively. Whereas inter comparison between non-smokers of study and control group using Feulgen stain and inter comparison between smokers of study and control group, using Giemsa stain revealed statistically significant results with P value 0.0034 and 0.0004, respectively. Conclusion: This study revealed that the studied individuals belong to a risk group and should periodically undergo biological monitoring and proper care.

Expansion and exfoliation of graphite to form graphene

KAUST Repository

Patole, Shashikan P.; Da Costa, Pedro M. F. J.

2017-01-01

Graphene production methods are described based on subjecting non- covalent graphite intercalated compounds, such as graphite bisulfate, to expansion conditions such as shocks of heat and/or microwaves followed by turbulence-assisted exfoliation

Superhydrophilic graphite surfaces and water-dispersible graphite colloids by electrochemical exfoliation

Energy Technology Data Exchange (ETDEWEB)

Li, Yueh-Feng [Department of Chemical and Materials Engineering, National Central University, Jhongli, 320 Taiwan (China); Chen, Shih-Ming; Lai, Wei-Hao [Materials and Chemical Research Laboratories, Industrial Technology Research Institute, Chutung, Hsinchu, 31040 Taiwan (China); Sheng, Yu-Jane [Department of Chemical Engineering, National Taiwan University, Taipei, 106 Taiwan (China); Tsao, Heng-Kwong [Department of Chemical and Materials Engineering, Department of Physics, National Central University, Jhongli, 320 Taiwan (China)

2013-08-14

Superhydrophilic graphite surfaces and water-dispersible graphite colloids are obtained by electrochemical exfoliation with hydrophobic graphite electrodes. Such counterintuitive characteristics are caused by partial oxidation and investigated by examining both graphite electrodes and exfoliated particles after electrolysis. The extent of surface oxidation can be explored through contact angle measurement, scanning electron microscope, electrical sheet resistance, x-ray photoelectron spectroscopy, zeta-potential analyzer, thermogravimetric analysis, UV-visible, and Raman spectroscopy. The degree of wettability of the graphite anode can be altered by the electrolytic current and time. The water contact angle declines generally with increasing the electrolytic current or time. After a sufficient time, the graphite anode becomes superhydrophilic and its hydrophobicity can be recovered by peeling with adhesive tape. This consequence reveals that the anodic graphite is oxidized by oxygen bubbles but the oxidation just occurs at the outer layers of the graphite sheet. Moreover, the characteristics of oxidation revealed by UV peak shift, peak ratio between D and G bands, and negative zeta-potential indicate the presence of graphite oxide on the outer shell of the exfoliated colloids. However, thermogravimetric analysis for the extent of decomposition of oxygen functional groups verifies that the amount of oxygen groups is significantly less than that of graphite oxide prepared via Hummer method. The structure of this partially oxidized graphite may consist of a graphite core covered with an oxidized shell. The properties of the exfoliated colloids are also influenced by pH of the electrolytic solution. As pH is increased, the extent of oxidation descends and the thickness of oxidized shell decreases. Those results reveal that the degree of oxidation of exfoliated nanoparticles can be manipulated simply by controlling pH.

Inhaled tolafentrine reverses pulmonary vascular remodeling via inhibition of smooth muscle cell migration

Directory of Open Access Journals (Sweden)

Weissmann Norbert

2005-11-01

Full Text Available Abstract Background The aim of the study was to assess the chronic effects of combined phosphodiesterase 3/4 inhibitor tolafentrine, administered by inhalation, during monocrotaline-induced pulmonary arterial hypertension (PAH in rats. Methods CD rats were given a single subcutaneous injection of monocrotaline to induce PAH. Four weeks after, rats were subjected to inhalation of tolafentrine or sham nebulization in an unrestrained, whole body aerosol exposure system. In these animals (i the acute pulmonary vasodilatory efficacy of inhaled tolafentrine (ii the anti-remodeling effect of long-term inhalation of tolafentrine (iii the effects of tolafentrine on the expression profile of 96 genes encoding cell adhesion and extracellular matrix regulation were examined. In addition, the inhibitory effect of tolafentrine on ex vivo isolated pulmonary artery SMC cell migration was also investigated. Results Monocrotaline injection provoked severe PAH (right ventricular systolic pressure increased from 25.9 ± 4.0 to 68.9 ± 3.2 after 4 weeks and 74.9 ± 5.1 mmHg after 6 weeks, cardiac output depression and right heart hypertrophy. The media thickness of the pulmonary arteries and the proportion of muscularization of small precapillary resistance vessels increased dramatically, and the migratory response of ex-vivo isolated pulmonary artery smooth muscle cells (PASMC was increased. Micro-arrays and subsequent confirmation with real time PCR demonstrated upregulation of several extracellular matrix regulation and adhesion genes, such as matrixmetalloproteases (MMP 2, 8, 9, 10, 11, 12, 20, Icam, Itgax, Plat and serpinb2. When chronically nebulized from day 28 to 42 (12 daily aerosol maneuvers, after full establishment of severe pulmonary hypertension, tolafentrine reversed about 60% of all hemodynamic abnormalities, right heart hypertrophy and monocrotaline-induced structural lung vascular changes, including the proportion of pulmonary artery

Ultrasound exfoliation of inorganic analogues of graphene

Czech Academy of Sciences Publication Activity Database

Štengl, Václav; Henych, Jiří; Slušná, Michaela; Ecorchard, Petra

2014-01-01

Roč. 9, APR (2014), s. 1-14 ISSN 1556-276X R&D Projects: GA ČR(CZ) GA14-05146S Institutional support: RVO:61388980 Keywords : Ultrasound * Exfoliation * Graphene inorganic analogues Subject RIV: CA - Inorganic Chemistry Impact factor: 2.779, year: 2014

Fibrosis of Two: Epithelial Cell-Fibroblast Interactions in Pulmonary Fibrosis

Science.gov (United States)

Sakai, Norihiko; Tager, Andrew M.

2013-01-01

Idiopathic pulmonary fibrosis (IPF) is characterized by the progressive and ultimately fatal accumulation of fibroblasts and extracellular matrix in the lung that distorts its architecture and compromises its function. IPF is now thought to result from wound-healing processes that, although initiated to protect the host from injurious environmental stimuli, lead to pathological fibrosis due to these processes becoming aberrant or over-exuberant. Although the environmental stimuli that trigger IPF remain to be identified, recent evidence suggests that they initially injure the alveolar epithelium. Repetitive cycles of epithelial injury and resultant alveolar epithelial cell death provoke the migration, proliferation, activation and myofibroblast differentiation of fibroblasts, causing the accumulation of these cells and the extracellular matrix that they synthesize. In turn, these activated fibroblasts induce further alveolar epithelial cell injury and death, thereby creating a vicious cycle of pro-fibrotic epithelial cell-fibroblast interactions. Though other cell types certainly make important contributions, we focus here on the “pas de deux” (steps of two), or perhaps more appropriate to IPF pathogenesis, the “folie à deux” (madness of two) of epithelial cells and fibroblasts that drives the progression of pulmonary fibrosis. We describe the signaling molecules that mediate the interactions of these cell types in their “fibrosis of two”, including transforming growth factor-β, connective tissue growth factor, sonic hedgehog, prostaglandin E2, angiotensin II and reactive oxygen species. PMID:23499992

CT manifestations of pulmonary Langerhans cell histiocytosis

International Nuclear Information System (INIS)

Qiang Jun; Yu Wei; Gao Wanqin; Song Haiqiao; Ma Yingjian

2010-01-01

Objective: To analyzes the CT manifestations of pulmonary Langerhans cell histiocytosis (PLCH). Methods: CT features of 11 patients with PLCH proved pathologically were analyzed retrospectively. Results: The main findings in 11 PLCHs were cysts and nodules. Two cases only had cysts, and 1 only had nodules, which most had cavitations. The other 8 cases showed cysts and nodules with 4 cases mainly manifested with cysts and nine mainly manifested with nodules. Two cases had pulmonary interstitial changes. One case only had cysts in the left upper lung field and 10 cases had lesions not only in the upper and middle but in the lower lung field, which 2 cases had more lesions in the lower and costo-phrenic angle field and 8 cases had less lesions in the costo-phrenic angle field. Three of these 8 cases had more lesions in the superior lobe and apical segment of lower lobe. Conclusion: CT manifestations of PLCH are helpful for the early diagnosis. (authors)

Ultrathin Topological Insulator Bi 2 Se 3 Nanoribbons Exfoliated by Atomic Force Microscopy

KAUST Repository

Hong, Seung Sae; Kundhikanjana, Worasom; Cha, Judy J.; Lai, Keji; Kong, Desheng; Meister, Stefan; Kelly, Michael A.; Shen, Zhi-Xun; Cui, Yi

2010-01-01

Ultrathin topological insulator nanostructures, in which coupling between top and bottom surface states takes place, are of great intellectual and practical importance. Due to the weak van der Waals interaction between adjacent quintuple layers (QLs), the layered bismuth selenide (Bi2Se 3), a single Dirac-cone topological insulator with a large bulk gap, can be exfoliated down to a few QLs. In this paper, we report the first controlled mechanical exfoliation of Bi2Se3 nanoribbons (>50 QLs) by an atomic force microscope (AFM) tip down to a single QL. Microwave impedance microscopy is employed to map out the local conductivity of such ultrathin nanoribbons, showing drastic difference in sheet resistance between 1-2 QLs and 4-5 QLs. Transport measurement carried out on an exfoliated (>5 QLs) Bi2Se3 device shows nonmetallic temperature dependence of resistance, in sharp contrast to the metallic behavior seen in thick (>50 QLs) ribbons. These AFM-exfoliated thin nanoribbons afford interesting candidates for studying the transition from quantum spin Hall surface to edge states. © 2010 American Chemical Society.

Preparation and characterization of self-assembly hydrogels with exfoliated montmorillonite nanosheets and chitosan

Science.gov (United States)

Wang, Wei; Zhao, Yunliang; Yi, Hao; Chen, Tianxing; Kang, Shichang; Li, Hongqiang; Song, Shaoxian

2018-01-01

Novel montmorillonite-nanosheet/chitosan (MMTNS/CS) hydrogels fabricated via the self-assembly of exfoliated MMTNS and CS chains were investigated. The exfoliation of MMTNS, self-assembly mechanism and structure of MMTNS/CS hydrogels were characterized by an atomic force microscope, scanning electron microscope, transmission electron microscope, Fourier transform infrared spectroscope, energy-dispersive x-ray spectroscope and Brunauer-Emmett-Teller analyzer, respectively. The results indicated that MMT could be easily exfoliated to nanosheets with a thickness of 1 ˜ 5 nm in aqueous solution by an ultrasonic base upon interlayer hydration. The formation mechanism of the self-assembly hydrogels was due to the hydrogen bond (-OH ··· +NH3-) and electrostatic interaction between the MMTNS and CS. The MMTNSs were connected consecutively by CS in-plane to form a huge slice. The porous structure of the hydrogels was controllable by adjusting the MMTNS/CS mass ratio. The hydrogels could be used as adsorbents for sewage treatments, carriers for drugs, microorganisms and catalyzers due to their controllable porous structure and tremendous specific surface area which were derived from the completely exfoliated MMTNS.

Ultrathin Topological Insulator Bi 2 Se 3 Nanoribbons Exfoliated by Atomic Force Microscopy

KAUST Repository

Hong, Seung Sae

2010-08-11

Ultrathin topological insulator nanostructures, in which coupling between top and bottom surface states takes place, are of great intellectual and practical importance. Due to the weak van der Waals interaction between adjacent quintuple layers (QLs), the layered bismuth selenide (Bi2Se 3), a single Dirac-cone topological insulator with a large bulk gap, can be exfoliated down to a few QLs. In this paper, we report the first controlled mechanical exfoliation of Bi2Se3 nanoribbons (>50 QLs) by an atomic force microscope (AFM) tip down to a single QL. Microwave impedance microscopy is employed to map out the local conductivity of such ultrathin nanoribbons, showing drastic difference in sheet resistance between 1-2 QLs and 4-5 QLs. Transport measurement carried out on an exfoliated (>5 QLs) Bi2Se3 device shows nonmetallic temperature dependence of resistance, in sharp contrast to the metallic behavior seen in thick (>50 QLs) ribbons. These AFM-exfoliated thin nanoribbons afford interesting candidates for studying the transition from quantum spin Hall surface to edge states. © 2010 American Chemical Society.

Endothelial progenitor cells in chronic obstructive pulmonary disease and emphysema

Science.gov (United States)

Tracy, Russell P.; Parikh, Megha A.; Hoffman, Eric A.; Shimbo, Daichi; Austin, John H. M.; Smith, Benjamin M.; Hueper, Katja; Vogel-Claussen, Jens; Lima, Joao; Gomes, Antoinette; Watson, Karol; Kawut, Steven; Barr, R. Graham

2017-01-01

Endothelial injury is implicated in the pathogenesis of COPD and emphysema; however the role of endothelial progenitor cells (EPCs), a marker of endothelial cell repair, and circulating endothelial cells (CECs), a marker of endothelial cell injury, in COPD and its subphenotypes is unresolved. We hypothesized that endothelial progenitor cell populations would be decreased in COPD and emphysema and that circulating endothelial cells would be increased. Associations with other subphenotypes were examined. The Multi-Ethnic Study of Atherosclerosis COPD Study recruited smokers with COPD and controls age 50–79 years without clinical cardiovascular disease. Endothelial progenitor cell populations (CD34+KDR+ and CD34+KDR+CD133+ cells) and circulating endothelial cells (CD45dimCD31+CD146+CD133-) were measured by flow cytometry. COPD was defined by standard spirometric criteria. Emphysema was assessed qualitatively and quantitatively on CT. Full pulmonary function testing and expiratory CTs were measured in a subset. Among 257 participants, both endothelial progenitor cell populations, and particularly CD34+KDR+ endothelial progenitor cells, were reduced in COPD. The CD34+KDR+CD133+ endothelial progenitor cells were associated inversely with emphysema extent. Both endothelial progenitor cell populations were associated inversely with extent of panlobular emphysema and positively with diffusing capacity. Circulating endothelial cells were not significantly altered in COPD but were inversely associated with pulmonary microvascular blood flow on MRI. There was no consistent association of endothelial progenitor cells or circulating endothelial cells with measures of gas trapping. These data provide evidence that endothelial repair is impaired in COPD and suggest that this pathological process is specific to emphysema. PMID:28291826

Nonredundant functions of alphabeta and gammadelta T cells in acrolein-induced pulmonary pathology.

Science.gov (United States)

Borchers, Michael T; Wesselkamper, Scott C; Eppert, Bryan L; Motz, Gregory T; Sartor, Maureen A; Tomlinson, Craig R; Medvedovic, Mario; Tichelaar, Jay W

2008-09-01

Acrolein exposure represents a significant human health hazard. Repeated acrolein exposure causes the accumulation of monocytes/macrophages and lymphocytes, mucous cell metaplasia, and epithelial injury. Currently, the mechanisms that control these events are unclear, and the relative contribution of T-cell subsets to pulmonary pathologies following repeated exposures to irritants is unknown. To examine whether lymphocyte subpopulations regulate inflammation and epithelial cell pathology, we utilized a mouse model of pulmonary pathology induced by repeated acrolein exposures. The role of lymphocyte subsets was examined by utilizing transgenic mice genetically deficient in either alphabeta T cells or gammadelta T cells, and changes in cellular, molecular, and pathologic outcomes associated with repeated inhalation exposure to 2.0 and 0.5 ppm acrolein were measured. To examine the potential functions of lymphocyte subsets, we purified these cells from the lungs of mice repeatedly exposed to 2.0 ppm acrolein, isolated and amplified messenger RNA, and performed microarray analysis. Our data demonstrate that alphabeta T cells are required for macrophage accumulation, whereas gammadelta T cells are critical regulators of epithelial cell homeostasis, as identified by epithelial cell injury and apoptosis, following repeated acrolein exposure. This is supported by microarray analyses that indicated the T-cell subsets are unique in their gene expression profiles following acrolein exposures. Microarray analyses identified several genes that may contribute to phenotypes mediated by T-cell subpopulations including those involved in cytokine receptor signaling, chemotaxis, growth factor production, lymphocyte activation, and apoptosis. These data provide strong evidence that T-cell subpopulations in the lung are major determinants of pulmonary pathology and highlight the advantages of dissecting their effector functions in response to toxicant exposures.

Loss of receptor on tuberculin-reactive T-cells marks active pulmonary tuberculosis.

Directory of Open Access Journals (Sweden)

Mathias Streitz

Full Text Available BACKGROUND: Tuberculin-specific T-cell responses have low diagnostic specificity in BCG vaccinated populations. While subunit-antigen (e.g. ESAT-6, CFP-10 based tests are useful for diagnosing latent tuberculosis infection, there is no reliable immunological test for active pulmonary tuberculosis. Notably, all existing immunological tuberculosis-tests are based on T-cell response size, whereas the diagnostic potential of T-cell response quality has never been explored. This includes surface marker expression and functionality of mycobacterial antigen specific T-cells. METHODOLOGY/PRINCIPAL FINDINGS: Flow-cytometry was used to examine over-night antigen-stimulated T-cells from tuberculosis patients and controls. Tuberculin and/or the relatively M. tuberculosis specific ESAT-6 protein were used as stimulants. A set of classic surface markers of T-cell naïve/memory differentiation was selected and IFN-gamma production was used to identify T-cells recognizing these antigens. The percentage of tuberculin-specific T-helper-cells lacking the surface receptor CD27, a state associated with advanced differentiation, varied considerably between individuals (from less than 5% to more than 95%. Healthy BCG vaccinated individuals had significantly fewer CD27-negative tuberculin-reactive CD4 T-cells than patients with smear and/or culture positive pulmonary tuberculosis, discriminating these groups with high sensitivity and specificity, whereas individuals with latent tuberculosis infection exhibited levels in between. CONCLUSIONS/SIGNIFICANCE: Smear and/or culture positive pulmonary tuberculosis can be diagnosed by a rapid and reliable immunological test based on the distribution of CD27 expression on peripheral blood tuberculin specific T-cells. This test works very well even in a BCG vaccinated population. It is simple and will be of great utility in situations where sputum specimens are difficult to obtain or sputum-smear is negative. It will also help

Detection of pulmonary hemorrhage with technetium-labeled red cells

International Nuclear Information System (INIS)

Winzelberg, G.G.; Laman, D.; Sachs, M.; Miller, W.H.

1981-01-01

Noninvasive techniques to aid in the diagnosis of massive pulmonary hemoptysis would be helpful in guiding more-invasive procedures such as bronchial artery angiography, which carries a risk of transverse myelitis. A patient was studied with technetium-labeled red cells and successfully detected a site of intermittent hemorrhage from the lung

Percolation scaling in composites of exfoliated MoS2 filled with nanotubes and graphene

NARCIS (Netherlands)

Cunningham, G.; Lotya, M.; McEvoy, N.; Duesberg, G.S.; Schoot, van der P.P.A.M.; Coleman, J.N.

2012-01-01

Applications of films of exfoliated layered compounds in many areas will be limited by their relatively low electrical conductivity. To address this, we have prepared and characterised composites of a nano-conductor (nanotubes or graphene) embedded in a matrix of exfoliated MoS2 nanosheets. Solvent

Immunomodulatory Role of Stem Cell from Human Exfoliated Deciduous Teeth on Periodontal Regeneration.

Science.gov (United States)

Gao, Xianling; Shen, Zongshan; Guan, Meiliang; Huang, Qiting; Chen, Lingling; Qin, Wei; Ge, Xiaohu; Chen, Haijia; Xiao, Yin; Lin, Zhengmei

2018-03-20

Periodontitis is initiated by the infection of periodontal bacteria and subsequent tissue inflammation due to immunoreaction, eventually leading to periodontal apparatus loss. Stem cells from human exfoliated deciduous teeth (SHEDs) have exhibited beneficial characteristics in dental tissue regeneration. However, the immunomodulatory functions of SHEDs have not been elucidated in the context of periodontitis treatment. In this study, we investigated the potential immunomodulatory effects of SHEDs on experimental periodontitis and demonstrated that multi-dose delivery of SHEDs led to periodontal tissue regeneration. SHEDs and monocytes/macrophages were cocultured in transwell systems and SHEDs were found to be capable of promoting monocyte/macrophages conversion to CD206+ M2-like phenotype. Bioluminescence imaging (BLI) was employed to assess the survival and distribution of SHEDs after delivery in periodontal tissues in an induced periodontitis model, and BLI revealed that SHEDs survived for approximately 7 days in periodontal tissues with little tissue diffusion. Then, multi-dose SHEDs delivery was applied to treat periodontitis at 7-day intervals. Results showed that muti-dose SHEDs altered the cytokine expression profile in gingival crevicular fluid, reduced gum bleeding, increased new attachment of periodontal ligament and decreased osteoclast differentiation. Micro-computed tomography analysis showed SHEDs administration significantly increased periodontal regeneration and alveolar bone volume, and decreased distance of cementoenamel junction to alveolar bone crest (CEJ-ABC). Furthermore, an increase in the number of CD206+ M2 macrophages was observed in periodontal tissues following the delivery of SHEDs, which aligned well with the promoted conversion to CD206+ M2-like cells from monocytes/macrophages in vitro after stimulation by SHEDs. This study demonstrated in a rat periodontitis model that local delivery of SHEDs attributed to the induction of M2

High-yield exfoliation of graphene using ternary-solvent strategy for detecting volatile organic compounds

Science.gov (United States)

Zhang, Shao-Lin; Zhang, Zhijun; Yang, Woo-Chul

2016-01-01

Despite the great progress in the theory and experimental verification we made in past decade, the practical application of graphene is still hindered by the lack of efficient, economical, scalable, ease-processing exfoliation method. Herein, we propose a facile, low-cost, and efficient liquid-phase exfoliation process using low boiling-temperature solvent mixture to fabricate few-layer graphene in large scale. The Hansen solubility parameter theory was applied to help optimize the composition of solvent mixture. Aqueous-based ternary-solvent mixture, for the first time, was adapted to exfoliate graphene. We demonstrate that the exfoliation efficiency using ternary-solvent mixture surpasses that from binary-solvent approach. The final product concentration after optimization was over 260 μg/ml. The concentrated graphene dispersion was used to fabricate gas sensor for detecting volatile organic gases. Taking advantage of large surface area, large number of adsorption sites, and well-preserved basal plane, the mass-produced graphene nanosheets exhibited promising sensing potential toward ethanol and methanol vapors.

Sequential structural and optical evolution of MoS2 by chemical synthesis and exfoliation

Science.gov (United States)

Kim, Ju Hwan; Kim, Jungkil; Oh, Si Duck; Kim, Sung; Choi, Suk-Ho

2015-06-01

Various types of MoS2 structures are successfully obtained by using economical and facile sequential synthesis and exfoliation methods. Spherically-shaped lumps of multilayer (ML) MoS2 are prepared by using a conventional hydrothermal method and were subsequently 1st-exfoliated in hydrazine while being kept in autoclave to be unrolled and separated into five-to-six-layer MoS2 pieces of several-hundred nm in size. The MoS2 MLs are 2nd-exfoliated in sodium naphthalenide under an Ar ambient to finally produce bilayer MoS2 crystals of ~100 nm. The sequential exfoliation processes downsize MoS2 laterally and reduce its number of layers. The three types of MoS2 allotropes exhibit particular optical properties corresponding to their structural differences. These results suggest that two-dimensional MoS2 crystals can be prepared by employing only chemical techniques without starting from high-pressure-synthesized bulk MoS2 crystals.

Hypoxia-Induced Mitogenic Factor (HIMF/FIZZ1/RELM?) Recruits Bone Marrow-Derived Cells to the Murine Pulmonary Vasculature

OpenAIRE

Angelini, Daniel J.; Su, Qingning; Kolosova, Irina A.; Fan, Chunling; Skinner, John T.; Yamaji-Kegan, Kazuyo; Collector, Michael; Sharkis, Saul J.; Johns, Roger A.

2010-01-01

Background Pulmonary hypertension (PH) is a disease of multiple etiologies with several common pathological features, including inflammation and pulmonary vascular remodeling. Recent evidence has suggested a potential role for the recruitment of bone marrow-derived (BMD) progenitor cells to this remodeling process. We recently demonstrated that hypoxia-induced mitogenic factor (HIMF/FIZZ1/RELM?) is chemotactic to murine bone marrow cells in vitro and involved in pulmonary vascular remodeling ...

Protective role of NKT cells and macrophage M2-driven phenotype in bleomycin-induced pulmonary fibrosis.

Science.gov (United States)

Grabarz, Felipe; Aguiar, Cristhiane Favero; Correa-Costa, Matheus; Braga, Tárcio Teodoro; Hyane, Meire I; Andrade-Oliveira, Vinícius; Landgraf, Maristella Almeida; Câmara, Niels Olsen Saraiva

2018-04-01

Pulmonary fibrosis is a result of an abnormal wound healing in lung tissue triggered by an excessive accumulation of extracellular matrix proteins, loss of tissue elasticity, and debit of ventilatory function. NKT cells are a major source of Th1 and Th2 cytokines and may be crucial in the polarization of M1/M2 macrophages in pulmonary fibrogenesis. Although there appears to be constant scientific progress in that field, pulmonary fibrosis still exhibits no current cure. From these facts, we hypothesized that NKT cells could influence the development of pulmonary fibrosis via modulation of macrophage activation. Wild type (WT) and NKT type I cell-deficient mice (Jα18 -/- ) were subjected to the protocol of bleomycin-induced pulmonary fibrosis with or without treatment with NKT cell agonists α-galactosylceramide and sulfatide. The participation of different cell populations, collagen deposition, and protein levels of different cytokines involved in inflammation and fibrosis was evaluated. The results indicate a benign role of NKT cells in Jα18 -/- mice and in wild-type α-galactosylceramide-sulfatide-treated groups. These animals presented lower levels of collagen deposition, fibrogenic molecules such as TGF-β and vimentin and improved survival rates. In contrast, WT mice developed a Th2-driven response augmenting IL-4, 5, and 13 protein synthesis and increased collagen deposition. Furthermore, the arginase-1 metabolic pathway was downregulated in wild-type NKT-activated and knockout mice indicating lower activity of M2 macrophages in lung tissue. Hence, our data suggest that NKT cells play a protective role in this experimental model by down modulating the Th2 milieu, inhibiting M2 polarization and finally preventing fibrosis.

New insight of high temperature oxidation on self-exfoliation capability of graphene oxide

Science.gov (United States)

Liu, Yuhang; Zeng, Jie; Han, Di; Wu, Kai; Yu, Bowen; Chai, Songgang; Chen, Feng; Fu, Qiang

2018-05-01

The preparation of graphene oxide (GO) via Hummers method is usually divided into two steps: low temperature oxidation at 35 °C (step I oxidation) and high temperature oxidation at 98 °C (step II oxidation). However, the effects of these two steps on the exfoliation capability and chemical structure of graphite oxide remain unclear. In this study, both the functional group content of graphite oxide and the entire evolution of interlayer spacing were investigated during the two steps. Step I oxidation is a slowly inhomogeneous oxidation step to remove unoxidized graphite flakes. The prepared graphite oxide can be easily self-exfoliated but contains a lot of organic sulfur. During the first 20 min of step II oxidation, the majority of organic sulfur can be efficiently removed and graphite oxide still remains a good exfoliation capability due to sharp increasing of carboxyl groups. However, with a longer oxidation time at step II oxidation, the decrease of organic sulfur content is slowed down apparently but without any carboxyl groups forming, then graphite oxide finally loses self-exfoliation capability. It is concluded that a short time of step II oxidation can produce purer and ultralarge GO sheets via self-exfoliation. The pure GO is possessed with better thermal stability and liquid crystal behavior. Besides, reduced GO films prepared from step II oxidation show better mechanical and electric properties after reducing compared with that obtained only via step I oxidation.

ROCK2 mediates the proliferation of pulmonary arterial endothelial cells induced by hypoxia in the development of pulmonary arterial hypertension

OpenAIRE

QIAO, FENG; ZOU, ZHITIAN; LIU, CHUNHUI; ZHU, XIAOFENG; WANG, XIAOQIANG; YANG, CHENGPENG; JIANG, TENGJIAO; CHEN, YING

2016-01-01

It has been reported that RhoA activation and Rho-kinase (ROCK) expression are increased in chronic hypoxic lungs, and the long-term inhibition of ROCK markedly improves the survival of patients with pulmonary arterial hypertension (PAH). However, whether Rho-kinase α (ROCK2) participates in regulation of the growth of pulmonary arterial endothelial cells (PAECs) remains unknown. The aim of the present study was to investigate the effect of hypoxia on the proliferation of PAECs and the role o...

One-Pot Exfoliation of Graphite and Synthesis of Nanographene/Dimesitylporphyrin Hybrids

Science.gov (United States)

Bernal, M. Mar; Pérez, Emilio M.

2015-01-01

A simple one-pot process to exfoliate graphite and synthesize nanographene-dimesitylporphyrin hybrids has been developed. Despite the bulky mesityl groups, which are expected to hinder the efficient π–π stacking between the porphyrin core and graphene, the liquid-phase exfoliation of graphite is significantly favored by the presence of the porphyrins. Metallation of the porphyrin further enhances this effect. The resulting graphene/porphyrin hybrids were characterized by spectroscopy (UV-visible, fluorescence, and Raman) and microscopy (STEM, scanning transmission electron microscopy). PMID:25984598

Synthesis and Thermal Conductivity of Exfoliated Hexagonal Boron Nitride/Alumina Ceramic Composite

Science.gov (United States)

Hung, Ching-cheh; Hurst, Janet; Santiago, Diana; Lizcano, Maricela; Kelly, Marisabel

2017-01-01

Exfoliated hexagonal boron nitride (hBN)/alumina composite can be fabricated by following the process of (1) heating a mixture of hBN, AlCl3, and NaF in nitrogen for intercalation; (2) heating the intercalated product in air for exfoliation and at the same time converting the intercalate (AlCl3) into Al2O3, (3) rinsing the oxidized product, (4) coating individual exfoliated hBN platelets that contain Al2O3 with new layers of aluminum oxide, and finally, (5) hot pressing the product into the composite. The composite thus obtained has a composition of approximately 60 percent by weight hBN and 40 percent by weight alumina. Its in-plane and through-plane thermal conductivity were measured to be 86 and 18 watts per meter Kelvin, respectively, at room temperature.

Bleomycin induced pulmonary to cytotoxicity in patients with germ cell tumours

International Nuclear Information System (INIS)

Usman, M.; Faruqui, Z.S.; Din, N.U.

2010-01-01

Background: Bleomycin is a cytotoxic drug used in treatment of Germ Cell Tumours (GCTs) and is associated with pulmonary toxicity. Bleomycin pulmonary toxicity (BPT) manifests predominantly as pulmonary fibrosis, organising pneumonia (OP) or Nonspecific Interstitial Pneumonitis (NSIP). Our objectives were to determine the incidence of BPT, describe the common HRCT patterns of pulmonary toxicity and to find out the correlation of variables (cumulative dose of bleomycin, age and glomerular filtration rate) with pulmonary toxicity. Methods: The study included the data of 96 patients from March 2006 to September 2008. All patients had histologically proven GCT and received bleomycin containing regimes. Variables age, GFR at the time of initial presentation along with cumulative dose of bleomycin at completion of chemotherapy or at the time of BPT were recorded. The High resolution CT chest (HRCT) of these patients was independently reviewed by two radiologists. Bleomycin toxicity was reported on the radiologic features of pulmonary fibrosis, OP or NSIP. Results : Fourteen patients (14.6%) developed BPT. Common patterns of BPT were, pulmonary fibrosis (5.2%), OP (5.2%) and NSIP (4.2%). Using the Univariate regression analysis there was significant relationship between BPT and age, cumulative bleomycin dose an d initial GFR at the beginning of treatment. Conclusions: Because BPT can be progressive and fatal, early recognition is important. The diagnosis of pulmonary toxicity should be considered in any patient with new or progressive respiratory complaints. BPT can be difficult to diagnose; therefore, knowledge and understanding of radiologic manifestations of toxicity caused by Bleomycin are necessary for institution of appropriate treatment. There is increasing incidence of BPT with increasing age, cumulative dose and decreasing GFR. (author)

Circulating microparticles in severe pulmonary arterial hypertension increase intercellular adhesion molecule-1 expression selectively in pulmonary artery endothelium

Directory of Open Access Journals (Sweden)

Leslie A. Blair

2016-10-01

Full Text Available Abstract Background Microparticles (MPs stimulate inflammatory adhesion molecule expression in systemic vascular diseases, however it is unknown whether circulating MPs stimulate localized ICAM-1 expression in the heterogeneically distinct pulmonary endothelium during pulmonary arterial hypertension (PAH. Pulmonary vascular lesions with infiltrating inflammatory cells in PAH form in the pulmonary arteries and arterioles, but not the microcirculation. Therefore, we sought to determine whether circulating MPs from PAH stimulate pulmonary artery endothelial cell-selective ICAM-1 expression. Results Pulmonary artery endothelial cells (PAECs were exposed to MPs isolated from the circulation of a rat model of severe PAH. During late-stage (8-weeks PAH, but not early-stage (3-weeks, an increase in ICAM-1 was observed. To determine whether PAH MP-induced ICAM-1 was selective for a specific segment of the pulmonary circulation, pulmonary microvascular endothelial cells (PMVECs were exposed to late-stage PAH MPs and no increase in ICAM-1 was detected. A select population of circulating MPs, the late-stage endoglin + MPs, were used to assess their ability to stimulate ICAM-1 and it was determined that the endoglin + MPs were sufficient to promote ICAM-1 increases in the whole cell, but not surface only expression. Conclusions Late-stage, but not early-stage, MPs in a model of severe PAH selectively induce ICAM-1 in pulmonary artery endothelium, but not pulmonary microcirculation. Further, the selected endoglin + PAH MPs, but not endoglin + MPs from control, are sufficient to promote whole cell ICAM-1 in PAECs. The implications of this work are that MPs in late-stage PAH are capable of inducing ICAM-1 expression selectively in the pulmonary artery. ICAM-1 likely plays a significant role in the observed inflammatory cell recruitment, specifically to vascular lesions in the pulmonary artery and not the pulmonary microcirculation.

Hypoxia, leukocytes, and the pulmonary circulation.

Science.gov (United States)

Stenmark, Kurt R; Davie, Neil J; Reeves, John T; Frid, Maria G

2005-02-01

Data are rapidly accumulating in support of the idea that circulating monocytes and/or mononuclear fibrocytes are recruited to the pulmonary circulation of chronically hypoxic animals and that these cells play an important role in the pulmonary hypertensive process. Hypoxic induction of monocyte chemoattractant protein-1, stromal cell-derived factor-1, vascular endothelial growth factor-A, endothelin-1, and tumor growth factor-beta(1) in pulmonary vessel wall cells, either directly or indirectly via signals from hypoxic lung epithelial cells, may be a critical first step in the recruitment of circulating leukocytes to the pulmonary circulation. In addition, hypoxic stress appears to induce release of increased numbers of monocytic progenitor cells from the bone marrow, and these cells may have upregulated expression of receptors for the chemokines produced by the lung circulation, which thus facilitates their specific recruitment to the pulmonary site. Once present, macrophages/fibrocytes may exert paracrine effects on resident pulmonary vessel wall cells stimulating proliferation, phenotypic modulation, and migration of resident fibroblasts and smooth muscle cells. They may also contribute directly to the remodeling process through increased production of collagen and/or differentiation into myofibroblasts. In addition, they could play a critical role in initiating and/or supporting neovascularization of the pulmonary artery vasa vasorum. The expanded vasa network may then act as a conduit for further delivery of circulating mononuclear cells to the pulmonary arterial wall, creating a feedforward loop of pathological remodeling. Future studies will need to determine the mechanisms that selectively induce leukocyte/fibrocyte recruitment to the lung circulation under hypoxic conditions, their direct role in the remodeling process via production of extracellular matrix and/or differentiation into myofibroblasts, their impact on the phenotype of resident smooth muscle

Surface Modification of Exfoliated Graphite Nano-Reinforcements, Phase II

Data.gov (United States)

National Aeronautics and Space Administration — Phase I results showed that two surface treatments, oxidative plasma and reactive finishes, are effective means of modifying the surface chemistry of exfoliated...

Calcified pulmonary thromboembolism in a child with sickle cell disease: value of multidetector CT in patients with acute chest syndrome

International Nuclear Information System (INIS)

Staser, Jonathan A.; Alam, Tariq; Applegate, Kimberly

2006-01-01

The incidence of pulmonary embolism in children is not clearly known, but is believed to be low. Risk factors for pulmonary thromboembolism include central venous catheter, malignancy, surgery, infection, trauma, and congenital hypercoagulable disorders. Children with sickle cell disease are prothrombotic and are at an increased risk of thromboembolism. The incidence of this event is unknown because these children are often not thoroughly imaged. We report here a case of a calcified pulmonary thromboembolism in a child with sickle cell disease and emphasize the use of multidetector CT in detection of pulmonary thromboembolism in children with sickle cell disease. (orig.)

Large and medium-sized pulmonary artery obstruction does not play a role of primary importance in the etiology of sickle-cell disease-associated pulmonary hypertension

NARCIS (Netherlands)

van Beers, Eduard J.; van Eck-Smit, Berthe L. F.; Mac Gillavry, Melvin R.; van Tuijn, Charlotte F. J.; van Esser, Joost W. J.; Brandjes, Dees P. M.; Kappers-Klunne, Mies C.; Duits, Ashley J.; Biemond, Bart J.; Schnog, John-John B.

2008-01-01

Background: Pulmonary hypertension (PHT) occurs in approximately 30% of adult patients with sickle-cell disease (SCD) and is a risk factor for early death. The potential role of pulmonary artery obstruction, whether due to emboli or in situ thrombosis, in the etiology of SCD-related PHT is unknown.

Chronic lymphocytic leukaemia manifestating as exfoliative dermatitis

Directory of Open Access Journals (Sweden)

Dhir R

1995-01-01

Full Text Available A 60-year-old patient reported with a history of redness and peeling of the skin, and sensations of chills and tightness of the skin of three months duration. Clinical examination revealed exfoliative dermatitis, generalised lymphadenopathy and hepatosplenomegely. A peripheral smear showed features of chronic lymphocytic leukaemia.

Study of surface exfoliation on 6H-SiC induced by H{sub 2}{sup +} implantation

Energy Technology Data Exchange (ETDEWEB)

Zhang, L. [Department of Physics, School of Science, Lanzhou University of Technology, Lanzhou 730050 (China); Li, B.S., E-mail: b.s.li@impcas.ac.cn [Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou 730000 (China)

2017-03-01

The effect of lattice damage generated by the H{sub 2}{sup +}-implantation on exfoliation efficiency in 6H-SiC wafers is investigated. <0001> 6H-SiC wafers were implanted with 134 keV H{sub 2}{sup +} ions to ion fluences from 1.5×10{sup 16} to 5×10{sup 16} H{sub 2}{sup +} cm{sup −2} and subsequently annealed at temperatures from 973 K to 1373 K. The samples were studied by a combination of optical microscopy and transmission electron microscopy. Only after 1373 K annealing for 15 min, blisters and exfoliation occur on the H{sub 2}{sup +}-implanted sample surface. With increasing the implantation fluences from 1.5×10{sup 16} to 3.75×10{sup 16} H{sub 2}{sup +} cm{sup −2}, the exfoliation mean size decreases, while the exfoliation density increases. For the highest fluence of 5×10{sup 16} H{sub 2}{sup +} cm{sup −2}, seldom exfoliations occur on the sample surface. Microstructure analysis shows that exfoliation efficiency is largely controlled by the H{sub 2}{sup +}-implantation-induced lattice damage. The depth of the microcrack is related to the implantation fluence. The effect of implantation fluence on dislocation loops, platelet nucleation and growth is investigated.

Exfoliation Propensity of Oxide Scale in Heat Exchangers Used for Supercritical CO2 Power Cycles

Energy Technology Data Exchange (ETDEWEB)

Sabau, Adrian S [ORNL; Shingledecker, John P. [Electric Power Research Institute (EPRI); Kung, Steve [Electric Power Research Institute (EPRI); Wright, Ian G. [WrightHT, Inc.; Nash, Jim [Brayton Energy, LLC, Hampton, NH

2016-01-01

Supercritical CO2 (sCO2) Brayton cycle systems offer the possibility of improved efficiency in future fossil energy power generation plants operating at temperatures of 650 C and above. As there are few data on the oxidation/corrosion behavior of structural alloys in sCO2 at these temperatures, modeling to predict the propensity for oxide exfoliation is not well developed, thus hindering materials selection for these novel cycles. The ultimate goal of this effort is to provide needed data on scale exfoliation behavior in sCO2 for confident alloy selection. To date, a model developed by ORNL and EPRI for the exfoliation of oxide scales formed on boiler tubes in high-temperature, high-pressure steam has proven useful for managing exfoliation in conventional steam plants. A major input provided by the model is the ability to predict the likelihood of scale failure and loss based on understanding of the evolution of the oxide morphologies and the conditions that result in susceptibility to exfoliation. This paper describes initial steps taken to extend the existing model for exfoliation of steam-side oxide scales to sCO2 conditions. The main differences between high-temperature, high-pressure steam and sCO2 that impact the model involve (i) significant geometrical differences in the heat exchangers, ranging from standard pressurized tubes seen typically in steam-producing boilers to designs for sCO2 that employ variously-curved thin walls to create shaped flow paths for extended heat transfer area and small channel cross-sections to promote thermal convection and support pressure loads; (ii) changed operating characteristics with sCO2 due to the differences in physical and thermal properties compared to steam; and (iii) possible modification of the scale morphologies, hence properties that influence exfoliation behavior, due to reaction with carbon species from sCO2. The numerical simulations conducted were based on an assumed sCO2 operating schedule and several

Demonstration of different endocervical staining methods and their usefulness in the diagnosis of the chlamydial infection in exfoliated cells advantages and disadvantages.

Science.gov (United States)

Mahmutović, Sabina; Beslagić, Edina; Hamzić, Sadeta; Aljicević, Mufida

2004-02-01

Microscopic demonstration of chlamydial inclusions within cells offered the first laboratory procedure supporting the clinical diagnosis of chlamydial infection. Our aim is to evaluate the usefulness of different endocervical staining methods in diagnosis of Chlamydia trachomatis (CT) infection within exfoliated cells of the endocervix. The cytological test for the detection of chlamydial inclusions in genital tract infection, though not as sensitive and specific as isolation in the cell culture monolayers, is still of the diagnostic value. The present study discusses the collection of clinical smears for microscopic examination, their preparation; fixation and staining of slides by a variety of staining methods that have been used to detect Chlamydia in clinical smears and biopsies. Most of these methods such as Giemsa stain, Papanicolaou, iodine, and immunofluorescence (IF) using monoclonal antibodies, are based on the combination of dyes designed to obtain optimum differentiation of the various structures. The utilization of different endocervical smear stains together with the clinical information can be used to identify women at high risk for CT infection.

Pulmonary toxicity of cytostatic drugs: cell kinetics

International Nuclear Information System (INIS)

Witschi, H.; Godfrey, G.; Frome, E.; Lindenschmidt, R.C.

1987-01-01

Mice were treated with three cytostatic drugs: cyclophosphamide, busulfan, or 1,3-bis(2-chloroethyl)-1-nitrosourea (BCNU). The alveolar labeling index was measured following drug administration with a pulse of 3 H-labeled thymidine and autoradiography. In cyclophosphamide-treated animals, peak alveolar cell proliferation was seen 5 days after injection of the drug. In animals treated with busulfan or BCNU, proliferation was even more delayed (occurring 2-3 weeks after administration). In contrast, with oleic acid, the highest alveolar cell labeling was found 2 days after intravenous administration. In animals exposed to a cytostatic drug, proliferation of type II alveolar cells was never a prominent feature whereas in animals treated with oleic acid there was an initial burst of type II cell proliferation. It is concluded that the patterns of pulmonary repair vary between chemicals designed to interfere with DNA replication as compared to agents which produce acute lung damage such as oleic acid

Exfoliated graphite/titanium dioxide nanocomposites for photodegradation of eosin yellow

International Nuclear Information System (INIS)

Ndlovu, Thabile; Kuvarega, Alex T.; Arotiba, Omotayo A.; Sampath, Srinivasan; Krause, Rui W.; Mamba, Bhekie B.

2014-01-01

Graphical abstract: - Highlights: • Preparation of exfoliated graphite (EG) from natural graphite. • Sol–gel anchoring of TiO 2 on exfoliated graphite. • High adsorption and photoactivity was observed for the EG-TiO 2 nanocomposite. • Mechanism of enhancement was proposed. - Abstract: An improved photocatalyst consisting of a nanocomposite of exfoliated graphite and titanium dioxide (EG-TiO 2 ) was prepared. SEM and TEM micrographs showed that the spherical TiO 2 nanoparticles were evenly distributed on the surface of the EG sheets. A four times photocatalytic enhancement was observed for this floating nanocomposite compared to TiO 2 and EG alone for the degradation of eosin yellow. For all the materials, the reactions followed first order kinetics where for EG-TiO 2 , the rate constant was much higher than for EG and TiO 2 under visible light irradiation. The enhanced photocatalytic activity of EG-TiO 2 was ascribed to the capability of graphitic layers to accept and transport electrons from the excited TiO 2 , promoting charge separation. This indicates that carbon, a cheap and abundant material, can be a good candidate as an electron attracting reservoir for photocatalytic organic pollutant degradation

Pulmonary CCR2+CD4+ T cells are immune regulatory and attenuate lung fibrosis development.

Science.gov (United States)

Milger, Katrin; Yu, Yingyan; Brudy, Eva; Irmler, Martin; Skapenko, Alla; Mayinger, Michael; Lehmann, Mareike; Beckers, Johannes; Reichenberger, Frank; Behr, Jürgen; Eickelberg, Oliver; Königshoff, Melanie; Krauss-Etschmann, Susanne

2017-11-01

Animal models have suggested that CCR2-dependent signalling contributes to the pathogenesis of pulmonary fibrosis, but global blockade of CCL2 failed to improve the clinical course of patients with lung fibrosis. However, as levels of CCR2 + CD4 + T cells in paediatric lung fibrosis had previously been found to be increased, correlating with clinical symptoms, we hypothesised that distinct CCR2 + cell populations might either increase or decrease disease pathogenesis depending on their subtype. To investigate the role of CCR2 + CD4 + T cells in experimental lung fibrosis and in patients with idiopathic pulmonary fibrosis and other fibrosis. Pulmonary CCR2 + CD4 + T cells were analysed using flow cytometry and mRNA profiling, followed by in silico pathway analysis, in vitro assays and adoptive transfer experiments. Frequencies of CCR2 + CD4 + T cells were increased in experimental fibrosis-specifically the CD62L - CD44 + effector memory T cell phenotype, displaying a distinct chemokine receptor profile. mRNA profiling of isolated CCR2 + CD4 + T cells from fibrotic lungs suggested immune regulatory functions, a finding that was confirmed in vitro using suppressor assays. Importantly, adoptive transfer of CCR2 + CD4 + T cells attenuated fibrosis development. The results were partly corroborated in patients with lung fibrosis, by showing higher percentages of Foxp3 + CD25 + cells within bronchoalveolar lavage fluid CCR2 + CD4 + T cells as compared with CCR2 - CD4 + T cells. Pulmonary CCR2 + CD4 + T cells are immunosuppressive, and could attenuate lung inflammation and fibrosis. Therapeutic strategies completely abrogating CCR2-dependent signalling will therefore also eliminate cell populations with protective roles in fibrotic lung disease. This emphasises the need for a detailed understanding of the functions of immune cell subsets in fibrotic lung disease. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2017. All rights

Decolorizing of azo dye Reactive red 24 aqueous solution using exfoliated graphite and H2O2 under ultrasound irradiation.

Science.gov (United States)

Li, Mei; Li, Ji-Tai; Sun, Han-Wen

2008-07-01

At its natural pH (6.95), the decolorization of Reactive red 24 in ultrasound, ultrasound/H2O2, exfoliated graphite, ultrasound/exfoliated graphite, exfoliated graphite/H2O2 and ultrasound/exfoliated graphite/H2O2 systems were compared. An enhancement was observed for the decolorization in ultrasound/exfoliated graphite/H2O2 system. The effect of solution pH, H2O2 and exfoliated graphite dosages, and temperature on the decolorization of Reactive red 24 was investigated. The sonochemical treatment in combination with exfoliated graphite/H2O2 showed a synergistic effect for the decolorization of Reactive red 24. The results indicated that under proper conditions, there was a possibility to remove Reactive red 24 very efficient from aqueous solution. The decolorization of other azo dyes (Reactive red 2, Methyl orange, Acid red 1, Acid red 73, Acid red 249, Acid orange 7, Acid blue 113, Acid brown 75, Acid green 20, Acid yellow 42, Acid mordant brown 33, Acid mordant yellow 10 and Direct green 1) was also investigated, at their natural pH.

The Role of Mitochondrial DNA in Mediating Alveolar Epithelial Cell Apoptosis and Pulmonary Fibrosis

Science.gov (United States)

Kim, Seok-Jo; Cheresh, Paul; Jablonski, Renea P.; Williams, David B.; Kamp, David W.

2015-01-01

Convincing evidence has emerged demonstrating that impairment of mitochondrial function is critically important in regulating alveolar epithelial cell (AEC) programmed cell death (apoptosis) that may contribute to aging-related lung diseases, such as idiopathic pulmonary fibrosis (IPF) and asbestosis (pulmonary fibrosis following asbestos exposure). The mammalian mitochondrial DNA (mtDNA) encodes for 13 proteins, including several essential for oxidative phosphorylation. We review the evidence implicating that oxidative stress-induced mtDNA damage promotes AEC apoptosis and pulmonary fibrosis. We focus on the emerging role for AEC mtDNA damage repair by 8-oxoguanine DNA glycosylase (OGG1) and mitochondrial aconitase (ACO-2) in maintaining mtDNA integrity which is important in preventing AEC apoptosis and asbestos-induced pulmonary fibrosis in a murine model. We then review recent studies linking the sirtuin (SIRT) family members, especially SIRT3, to mitochondrial integrity and mtDNA damage repair and aging. We present a conceptual model of how SIRTs modulate reactive oxygen species (ROS)-driven mitochondrial metabolism that may be important for their tumor suppressor function. The emerging insights into the pathobiology underlying AEC mtDNA damage and apoptosis is suggesting novel therapeutic targets that may prove useful for the management of age-related diseases, including pulmonary fibrosis and lung cancer. PMID:26370974

NFATc3 and VIP in Idiopathic Pulmonary Fibrosis and Chronic Obstructive Pulmonary Disease.

Directory of Open Access Journals (Sweden)

Anthony M Szema

Full Text Available Idiopathic pulmonary fibrosis (IPF and chronic obstructive pulmonary disease (COPD are both debilitating lung diseases which can lead to hypoxemia and pulmonary hypertension (PH. Nuclear Factor of Activated T-cells (NFAT is a transcription factor implicated in the etiology of vascular remodeling in hypoxic PH. We have previously shown that mice lacking the ability to generate Vasoactive Intestinal Peptide (VIP develop spontaneous PH, pulmonary arterial remodeling and lung inflammation. Inhibition of NFAT attenuated PH in these mice suggesting a connection between NFAT and VIP. To test the hypotheses that: 1 VIP inhibits NFAT isoform c3 (NFATc3 activity in pulmonary vascular smooth muscle cells; 2 lung NFATc3 activation is associated with disease severity in IPF and COPD patients, and 3 VIP and NFATc3 expression correlate in lung tissue from IPF and COPD patients. NFAT activity was determined in isolated pulmonary arteries from NFAT-luciferase reporter mice. The % of nuclei with NFAT nuclear accumulation was determined in primary human pulmonary artery smooth muscle cell (PASMC cultures; in lung airway epithelia and smooth muscle and pulmonary endothelia and smooth muscle from IPF and COPD patients; and in PASMC from mouse lung sections by fluorescence microscopy. Both NFAT and VIP mRNA levels were measured in lungs from IPF and COPD patients. Empirical strategies applied to test hypotheses regarding VIP, NFATc3 expression and activity, and disease type and severity. This study shows a significant negative correlation between NFAT isoform c3 protein expression levels in PASMC, activity of NFATc3 in pulmonary endothelial cells, expression and activity of NFATc3 in bronchial epithelial cells and lung function in IPF patients, supporting the concept that NFATc3 is activated in the early stages of IPF. We further show that there is a significant positive correlation between NFATc3 mRNA expression and VIP RNA expression only in lungs from IPF patients

Heterocyclic aramid nanoparticle-assisted graphene exfoliation for fabrication of pristine graphene-based composite paper

Energy Technology Data Exchange (ETDEWEB)

Mo, Yao; Liu, Qi; Fan, Jinchen, E-mail: Jinchen.fan@shiep.edu.cn; Shi, Penghui; Min, Yulin, E-mail: ahaqmylin@126.com; Xu, Qunjie [Shanghai University of Electric Power, Shanghai Key Laboratory of Materials Protection and Advanced Materials in Electric Power, College of Environmental and Chemical Engineering (China)

2015-07-15

Mechanically strong, electrically conductive, and flexible pristine graphene-based composite paper was prepared based on heterocyclic aramid nanoparticle-assisted liquid-phase exfoliation of graphite. The macroscopic heterocyclic aramid yarns were split and assembled into heterocyclic aramid nanoparticles with the size of ∼30 nm by deprotonation in dimethylsulfoxide in the presence of potassium hydroxide. The obtained heterocyclic aramid nanoparticles dimethylsulfoxide dispersion was used as good medium solvent for highly efficiency liquid-phase exfoliation of graphite. The results demonstrated that the concentration of exfoliated graphene can facile reaches ∼2.72 mg/mL after direct sonication of 7 h with assist of heterocyclic aramid nanoparticles. After exfoliation, the self-assembled pristine graphene-based composite paper was fabricated by vacuum-assisted filtration. Due to the introduction of heterocyclic aramid nanoparticles, the self-assembled pristine graphene/heterocyclic aramid nanoparticles composite paper exhibited good mechanical property with tensile strength of ∼129.7 MPa, meantime, has a high electrical conductivity of ∼1.42 × 10{sup 4} S/m.

Heterocyclic aramid nanoparticle-assisted graphene exfoliation for fabrication of pristine graphene-based composite paper

International Nuclear Information System (INIS)

Mo, Yao; Liu, Qi; Fan, Jinchen; Shi, Penghui; Min, Yulin; Xu, Qunjie

2015-01-01

Mechanically strong, electrically conductive, and flexible pristine graphene-based composite paper was prepared based on heterocyclic aramid nanoparticle-assisted liquid-phase exfoliation of graphite. The macroscopic heterocyclic aramid yarns were split and assembled into heterocyclic aramid nanoparticles with the size of ∼30 nm by deprotonation in dimethylsulfoxide in the presence of potassium hydroxide. The obtained heterocyclic aramid nanoparticles dimethylsulfoxide dispersion was used as good medium solvent for highly efficiency liquid-phase exfoliation of graphite. The results demonstrated that the concentration of exfoliated graphene can facile reaches ∼2.72 mg/mL after direct sonication of 7 h with assist of heterocyclic aramid nanoparticles. After exfoliation, the self-assembled pristine graphene-based composite paper was fabricated by vacuum-assisted filtration. Due to the introduction of heterocyclic aramid nanoparticles, the self-assembled pristine graphene/heterocyclic aramid nanoparticles composite paper exhibited good mechanical property with tensile strength of ∼129.7 MPa, meantime, has a high electrical conductivity of ∼1.42 × 10 4  S/m.

High-resolution computed tomography findings in pulmonary Langerhans cell histiocytosis

Energy Technology Data Exchange (ETDEWEB)

Rodrigues, Rosana Souza [Universidade Federal do Rio de Janeiro (HUCFF/UFRJ), RJ (Brazil). Hospital Universitario Clementino Fraga Filho. Unit of Radiology; Capone, Domenico; Ferreira Neto, Armando Leao [Universidade do Estado do Rio de Janeiro (UERJ), Rio de Janeiro, RJ (Brazil)

2011-07-15

Objective: The present study was aimed at characterizing main lung changes observed in pulmonary Langerhans cell histiocytosis by means of high-resolution computed tomography. Materials and Methods: High-resolution computed tomography findings in eight patients with proven disease diagnosed by open lung biopsy, immunohistochemistry studies and/or extrapulmonary manifestations were retrospectively evaluated. Results: Small rounded, thin-walled cystic lesions were observed in the lung of all the patients. Nodules with predominantly peripheral distribution over the lung parenchyma were observed in 75% of the patients. The lesions were diffusely distributed, predominantly in the upper and middle lung fields in all of the cases, but involvement of costophrenic angles was observed in 25% of the patients. Conclusion: Comparative analysis of high-resolution computed tomography and chest radiography findings demonstrated that thinwalled cysts and small nodules cannot be satisfactorily evaluated by conventional radiography. Because of its capacity to detect and characterize lung cysts and nodules, high-resolution computed tomography increases the probability of diagnosing pulmonary Langerhans cell histiocytosis. (author)

Pulmonary Langerhans cell histiocytosis with cervical lymph node involvement, and coexistence with pulmonary tuberculosis and right pneumothorax: a case report and review of literature.

Science.gov (United States)

Gao, Limin; Li, Huifang; Li, Gandi; Liu, Weiping; Li, Jinnan; Zhang, Wenyan

2015-01-01

We report an uncommon 22-year-old male Pulmonary Langerhans Cell Histiocytosis (PLCH) case which co-existed with pulmonary tuberculosis (TB). Unlike the common PLCH cases, this PLCH case has cervical lymph node involvement and right pneumothorax. The diagnosis was established by the imaging of lung and the biopsies of the lung and left neck lymph node. Imaging of the chest showed characteristic small nodules and thin-walled cysts and right pneumothorax. The LCH cells in the lung and left neck lymph node were characterized by large convoluted nuclei with cerebriform indentations of the nuclear envelope and longitudinal grooves. The nuclei contained small eosinophilic nucleoli and moderate amount cytoplasm. Immunohistochemically, the histiocytoid cells were positive for Langerin, CD1a and S-100. Acid-fast bacilli were found in sputum and lung biopsy tissue. To the best of our knowledge, this is the first case of PLCH with cervical lymph node involvement, and coexisted with pulmonary tuberculosis, right pneumothorax. A contribution of this case and review three of the five cases of PLCH with extrapulmonary involvement to lymph nodes resolved spontaneously after smoking cessation constitute a novel addition that it is inappropriate to regard pulmonary/nodal LCH as multi-organ or disseminated disease, and the treatment methods are the same whether the PLCH patient with lymph node involvement or not.

High-Yield Preparation and Electrochemical Properties of Few-Layer MoS2 Nanosheets by Exfoliating Natural Molybdenite Powders Directly via a Coupled Ultrasonication-Milling Process

Science.gov (United States)

Dong, Huina; Chen, Deliang; Wang, Kai; Zhang, Rui

2016-09-01

Cost-effective and scalable preparation of two-dimensional (2D) molybdenum disulfide (MoS2) has been the bottleneck that limits their applications. This paper reports a novel coupled ultrasonication-milling (CUM) process to exfoliate natural molybdenite powders to achieve few-layer MoS2 (FL-MoS2) nanosheets in the solvent of N-methyl-2-pyrrolidone (NMP) with polyvinylpyrrolidone (PVP) molecules. The synergistic effect of ultrasonication and sand milling highly enhanced the exfoliation efficiency, and the precursor of natural molybdenite powders minimizes the synthetic cost of FL-MoS2 nanosheets. The exfoliation of natural molybdenite powders was conducted in a home-made CUM system, mainly consisting of an ultrasonic cell disruptor and a ceramic sand mill. The samples were characterized by X-ray diffraction, UV-vis spectra, Raman spectra, FT-IR, SEM, TEM, AFM, and N2 adsorption-desorption. The factors that influence the exfoliation in the CUM process, including the initial concentration of natural molybdenite powders ( C in, 15-55 g L-1), ultrasonic power ( P u, 200-350 W), rotation speed of sand mill ( ω s, 1500-2250 r.p.m), exfoliation time ( t ex, 0.5-6 h), and the molar ratio of PVP unit to MoS2 ( R pm, 0-1), were systematically investigated. Under the optimal CUM conditions (i.e., C in = 45 g L-1, P u = 280 W, ω s = 2250 r.p.m and R pm = 0.5), the yield at t ex = 6 h reaches 21.6 %, and the corresponding exfoliation rate is as high as 1.42 g L-1 h-1. The exfoliation efficiency of the CUM mode is much higher than that of either the ultrasonication (U) mode or the milling (M) mode. The synergistic mechanism and influencing rules of the CUM process in exfoliating natural molybdenite powders were elaborated. The as-obtained FL-MoS2 nanosheets have a high specific surface area of 924 m2 g-1 and show highly enhanced electrocatalytic performance in hydrogen evolution reaction and good electrochemical sensing property in detecting ascorbic acid. The CUM process

Synthesis of SnSe nanosheets by hydrothermal intercalation and exfoliation route and their photoresponse properties

Energy Technology Data Exchange (ETDEWEB)

Ren, Xiaohui; Qi, Xiang, E-mail: xqi@xtu.edu.cn; Shen, Yongzhen; Xu, Guanghua; Li, Jun; Li, Zhenqing; Huang, Zongyu; Zhong, Jianxin

2016-12-15

Two dimensional Tin Selenide (SnSe) nanosheets (NSs) have been prepared via a facile hydrothermal intercalation and exfoliation route. Morphological test verifies high yield of SnSe NSs with good quality. Additional X-ray diffraction pattern and Raman spectra are carried out and confirm the exfoliated SnSe nanosheet is pure and well crystalized. AFM measurement, along with the SEM images and Raman shifts, reveals few-layers SnSe nanosheet has been successfully obtained after hydrothermal intercalation and exfoliation route. Photoelectrochemical tests also demonstrate the photocurrent density of SnSe NSs is greatly improved compare to that of bulk SnSe. Photocurrent density of exfoliated SnSe NSs can achieve 16 μA/cm{sup 2} when the applied potential is 0.8 V, which is nearly four times higher than that of bulk SnSe. This work demonstrates that the two-dimensional SnSe NSs may have a great potential application in photovoltaic devices.

Synthesis of SnSe nanosheets by hydrothermal intercalation and exfoliation route and their photoresponse properties

International Nuclear Information System (INIS)

Ren, Xiaohui; Qi, Xiang; Shen, Yongzhen; Xu, Guanghua; Li, Jun; Li, Zhenqing; Huang, Zongyu; Zhong, Jianxin

2016-01-01

Two dimensional Tin Selenide (SnSe) nanosheets (NSs) have been prepared via a facile hydrothermal intercalation and exfoliation route. Morphological test verifies high yield of SnSe NSs with good quality. Additional X-ray diffraction pattern and Raman spectra are carried out and confirm the exfoliated SnSe nanosheet is pure and well crystalized. AFM measurement, along with the SEM images and Raman shifts, reveals few-layers SnSe nanosheet has been successfully obtained after hydrothermal intercalation and exfoliation route. Photoelectrochemical tests also demonstrate the photocurrent density of SnSe NSs is greatly improved compare to that of bulk SnSe. Photocurrent density of exfoliated SnSe NSs can achieve 16 μA/cm"2 when the applied potential is 0.8 V, which is nearly four times higher than that of bulk SnSe. This work demonstrates that the two-dimensional SnSe NSs may have a great potential application in photovoltaic devices.

High-yield exfoliation of tungsten disulphide nanosheets by rational mixing of low-boiling-point solvents

Science.gov (United States)

Sajedi-Moghaddam, Ali; Saievar-Iranizad, Esmaiel

2018-01-01

Developing high-throughput, reliable, and facile approaches for producing atomically thin sheets of transition metal dichalcogenides is of great importance to pave the way for their use in real applications. Here, we report a highly promising route for exfoliating two-dimensional tungsten disulphide sheets by using binary combination of low-boiling-point solvents. Experimental results show significant dependence of exfoliation yield on the type of solvents as well as relative volume fraction of each solvent. The highest yield was found for appropriate combination of isopropanol/water (20 vol% isopropanol and 80 vol% water) which is approximately 7 times higher than that in pure isopropanol and 4 times higher than that in pure water. The dramatic increase in exfoliation yield can be attributed to perfect match between the surface tension of tungsten disulphide and binary solvent system. Furthermore, solvent molecular size also has a profound impact on the exfoliation efficiency, due to the steric repulsion.

Genetic damage in exfoliated cells from oral mucosa of individuals exposed to X-rays during panoramic dental radiographies.

Science.gov (United States)

Cerqueira, E M M; Gomes-Filho, I S; Trindade, S; Lopes, M A; Passos, J S; Machado-Santelli, G M

2004-08-08

The genotoxic effects of X-ray emitted during dental panoramic radiography were evaluated in exfoliated cells from oral epithelium through a differentiated protocol of the micronucleus test. Thirty-one healthy individuals agreed to participate in this study and were submitted to this procedure for diagnosis purpose after being requested by the dentist. All of them answered a questionnaire before the examination. Cells were obtained from both sides of the cheek by gentle scrapping with a cervical brush, immediately before the exposure and after 10 days. Cytological preparations were stained according to Feulgen-Rossenbeck reaction and analyzed under light and laser scanning confocal microscopies. Micronuclei, nuclear projections (buds and broken eggs) and degenerative nuclear alterations (condensed chromatin, karyolysis and karyorrhexis) were scored. The frequencies of micronuclei, karyolysis and pycnosis were similar before and after exposure (P > 0.90), whereas the condensation of the chromatin and the karyorrhexis increased significantly after exposure (P structures are associated to the normal epithelium differentiation. The results suggest that the X-ray exposure during panoramic dental radiography induces a cytotoxic effect by increasing apoptosis. We also believe that the score of other nuclear alterations in addition to the micronucleus improves the sensitivity of genotoxic effects detection.

Intrauterine growth restriction decreases pulmonary alveolar and vessel growth and causes pulmonary artery endothelial cell dysfunction in vitro in fetal sheep

Science.gov (United States)

Seedorf, Gregory J.; Brown, Alicia; Roe, Gates; O'Meara, Meghan C.; Gien, Jason; Tang, Jen-Ruey; Abman, Steven H.

2011-01-01

Intrauterine growth restriction (IUGR) increases the risk for bronchopulmonary dysplasia (BPD). Abnormal lung structure has been noted in animal models of IUGR, but whether IUGR adversely impacts fetal pulmonary vascular development and pulmonary artery endothelial cell (PAEC) function is unknown. We hypothesized that IUGR would decrease fetal pulmonary alveolarization, vascular growth, and in vitro PAEC function. Studies were performed in an established model of severe placental insufficiency and IUGR induced by exposing pregnant sheep to elevated temperatures. Alveolarization, quantified by radial alveolar counts, was decreased 20% (P growth by 68% (P growth was reduced in IUGR PAECs by 29% at baseline (P growth and PAEC dysfunction in vitro. This may contribute to the increased risk for adverse respiratory outcomes and BPD in infants with IUGR. PMID:21873446

SPDEF is required for mouse pulmonary goblet cell differentiation and regulates a network of genes associated with mucus production

NARCIS (Netherlands)

Chen, G.; Korfhagen, T.R.; Xu, Y.; Kitzmiller, J.; Wert, S.E.; Maeda, Y.; Gregorieff, A.; Clevers, H.; Whitsett, J.A.

2009-01-01

Various acute and chronic inflammatory stimuli increase the number and activity of pulmonary mucus-producing goblet cells, and goblet cell hyperplasia and excess mucus production are central to the pathogenesis of chronic pulmonary diseases. However, little is known about the transcriptional

Age estimation using exfoliative cytology and radiovisiography: A comparative study.

Science.gov (United States)

Nallamala, Shilpa; Guttikonda, Venkateswara Rao; Manchikatla, Praveen Kumar; Taneeru, Sravya

2017-01-01

Age estimation is one of the essential factors in establishing the identity of an individual. Among various methods, exfoliative cytology (EC) is a unique, noninvasive technique, involving simple, and pain-free collection of intact cells from the oral cavity for microscopic examination. The study was undertaken with an aim to estimate the age of an individual from the average cell size of their buccal smears calculated using image analysis morphometric software and the pulp-tooth area ratio in mandibular canine of the same individual using radiovisiography (RVG). Buccal smears were collected from 100 apparently healthy individuals. After fixation in 95% alcohol, the smears were stained using Papanicolaou stain. The average cell size was measured using image analysis software (Image-Pro Insight 8.0). The RVG images of mandibular canines were obtained, pulp and tooth areas were traced using AutoCAD 2010 software, and area ratio was calculated. The estimated age was then calculated using regression analysis. The paired t -test between chronological age and estimated age by cell size and pulp-tooth area ratio was statistically nonsignificant ( P > 0.05). In the present study, age estimated by pulp-tooth area ratio and EC yielded good results.

Automotive body panel containing thermally exfoliated graphite oxide

Science.gov (United States)

Prud'Homme, Robert K. (Inventor); Aksay, Ilhan A. (Inventor); Adamson, Douglas (Inventor); Abdala, Ahmed (Inventor)

2011-01-01

An automotive body panel containing a polymer composite formed of at least one polymer and a modified graphite oxide material, which is a thermally exfoliated graphite oxide with a surface area of from about 300 m.sup.2/g to 2600 m.sup.2/g.

Group 2 Innate Lymphoid Cells in Pulmonary Immunity and Tissue Homeostasis

Directory of Open Access Journals (Sweden)

Barbara C. Mindt

2018-04-01

Full Text Available Group 2 innate lymphoid cells (ILC2 represent an evolutionary rather old but only recently identified member of the family of innate lymphoid cells and have received much attention since their detailed description in 2010. They can orchestrate innate as well as adaptive immune responses as they interact with and influence several immune and non-immune cell populations. Moreover, ILC2 are able to rapidly secrete large amounts of type 2 cytokines that can contribute to protective but also detrimental host immune responses depending on timing, location, and physiological context. Interestingly, ILC2, despite their scarcity, are the dominant innate lymphoid cell population in the lung, indicating a key role as first responders and amplifiers upon immune challenge at this site. In addition, the recently described tissue residency of ILC2 further underlines the importance of their respective microenvironment. In this review, we provide an overview of lung physiology including a description of the most prominent pulmonary resident cells together with a review of known and potential ILC2 interactions within this unique environment. We will further outline recent observations regarding pulmonary ILC2 during immune challenge including respiratory infections and discuss different models and approaches to study ILC2 biology in the lung.

Group 2 Innate Lymphoid Cells in Pulmonary Immunity and Tissue Homeostasis.

Science.gov (United States)

Mindt, Barbara C; Fritz, Jörg H; Duerr, Claudia U

2018-01-01

Group 2 innate lymphoid cells (ILC2) represent an evolutionary rather old but only recently identified member of the family of innate lymphoid cells and have received much attention since their detailed description in 2010. They can orchestrate innate as well as adaptive immune responses as they interact with and influence several immune and non-immune cell populations. Moreover, ILC2 are able to rapidly secrete large amounts of type 2 cytokines that can contribute to protective but also detrimental host immune responses depending on timing, location, and physiological context. Interestingly, ILC2, despite their scarcity, are the dominant innate lymphoid cell population in the lung, indicating a key role as first responders and amplifiers upon immune challenge at this site. In addition, the recently described tissue residency of ILC2 further underlines the importance of their respective microenvironment. In this review, we provide an overview of lung physiology including a description of the most prominent pulmonary resident cells together with a review of known and potential ILC2 interactions within this unique environment. We will further outline recent observations regarding pulmonary ILC2 during immune challenge including respiratory infections and discuss different models and approaches to study ILC2 biology in the lung.

Involvement of mast cells in monocrotaline-induced pulmonary hypertension in rats

NARCIS (Netherlands)

B.K. Dahal (Bhola); D. Kosanovic (Djuro); C. Kaulen (Christina); T. Cornitescu (Teodora); R. Savai (Rajkumar); J. Hoffmann (Julia); I.K.M. Reiss (Irwin); H.A. Ghofrani; N. Weissmann; W.M. Kuebler (Wolfgang); W. Seeger (Werner); F. Grimminger (Friedrich); R.T. Schermuly (Ralph Theo)

2011-01-01

textabstractBackground: Mast cells (MCs) are implicated in inflammation and tissue remodeling. Accumulation of lung MCs is described in pulmonary hypertension (PH); however, whether MC degranulation and c-kit, a tyrosine kinase receptor critically involved in MC biology, contribute to the

Hole-doping of mechanically exfoliated graphene by confined hydration layers

Institute of Scientific and Technical Information of China (English)

Tjeerd R. J. Bollmann[1,2; Liubov Yu. Antipina[3,4; Matthias Temmen[2; Michael Reichling[2; Pavel B. Sorokin[5

2015-01-01

By the use of non-contact atomic force microscopy （NC-AFM） and Kelvin probe force microscopy （KPFM）, we measure the local surface potential of mechanically exfoliated graphene on the prototypical insulating hydrophilic substrate of CAF2（111）. Hydration layers confined between the graphene and the CaF2 substrate, resulting from the graphene＇s preparation under ambient conditions on the hydrophilic substrate surface, are found to electronically modify the graphene as the material＇s electron density transfers from graphene to the hydration layer. Density functional theory （DFT） calculations predict that the first 2 to 3 water layers adjacent to the graphene hole-dope the graphene by several percent of a unit charge per unit cell.

Morphological, viscoelastic and mechanical characterization of polypropylene/exfoliated graphite nanocomposites

Energy Technology Data Exchange (ETDEWEB)

Ferreira, Creusa Iara; Oliveira, Ricardo Vinicius Bof de; Mauler, Raquel Santos, E-mail: raquel.mauler@ufrgs.br [Universidade Federal do Rio Grande do Sul (PGCIMAT/IQ/UFRGS), Porto Alegre, RS (Brazil); Bianchi, Otavio [Universidade de Caxias do Sul (PGMAT/CCET/UCS), RS (Brazil); Oviedo, Mauro Alfredo Soto [Braskem S/A, Rio de Janeiro, RJ (Brazil)

2013-07-01

The viscoelastic, mechanical and morphological properties of polypropylene/exfoliated graphite nanocomposites with different contents of nanofiller were investigated. According to transmission electron microscopy results, the nanofiller particles were homogeneously dispersed in the matrix. The rheological properties indicated that incorporation of graphite improved the matrix stiffness and had a reinforcing effect. Exfoliated graphite had a weak interaction with the polypropylene. The behavior of the nanocomposites was similar to that of polypropylene in terms of the interfacial detachment inferred from the transmission electron microscopy images and of their G' (storage) and G' (loss) moduli, and viscosity. The mechanical properties of the nanocomposites compared to the matrix improved significantly for the flexural and storage moduli with little loss of impact strength. (author)

Exfoliated graphite/titanium dioxide nanocomposites for photodegradation of eosin yellow

Energy Technology Data Exchange (ETDEWEB)

Ndlovu, Thabile, E-mail: atkuvarega@gmail.com [University of Swaziland, Department of Chemistry, Private Bag 4, Kwaluseni (Swaziland); Kuvarega, Alex T.; Arotiba, Omotayo A. [University of Johannesburg, Department of Applied Chemistry, P.O. Box 17011, Doornfontein 2028, Johannesburg (South Africa); Sampath, Srinivasan [Indian Institute of Science, Department of Inorganic and Physical Chemistry, Bangalore 560012 (India); Krause, Rui W. [Rhodes University, Department of Chemistry, P.O. Box 94, Grahamstown 6140 South Africa (South Africa); Mamba, Bhekie B., E-mail: bmamba@uj.ac.za [University of Johannesburg, Department of Applied Chemistry, P.O. Box 17011, Doornfontein 2028, Johannesburg (South Africa)

2014-05-01

Graphical abstract: - Highlights: • Preparation of exfoliated graphite (EG) from natural graphite. • Sol–gel anchoring of TiO{sub 2} on exfoliated graphite. • High adsorption and photoactivity was observed for the EG-TiO{sub 2} nanocomposite. • Mechanism of enhancement was proposed. - Abstract: An improved photocatalyst consisting of a nanocomposite of exfoliated graphite and titanium dioxide (EG-TiO{sub 2}) was prepared. SEM and TEM micrographs showed that the spherical TiO{sub 2} nanoparticles were evenly distributed on the surface of the EG sheets. A four times photocatalytic enhancement was observed for this floating nanocomposite compared to TiO{sub 2} and EG alone for the degradation of eosin yellow. For all the materials, the reactions followed first order kinetics where for EG-TiO{sub 2}, the rate constant was much higher than for EG and TiO{sub 2} under visible light irradiation. The enhanced photocatalytic activity of EG-TiO{sub 2} was ascribed to the capability of graphitic layers to accept and transport electrons from the excited TiO{sub 2}, promoting charge separation. This indicates that carbon, a cheap and abundant material, can be a good candidate as an electron attracting reservoir for photocatalytic organic pollutant degradation.

Graphene prepared by one-pot solvent exfoliation as a highly sensitive platform for electrochemical sensing

Energy Technology Data Exchange (ETDEWEB)

Wu, Can; Cheng, Qin [Key Laboratory for Large-Format Battery Materials and System, Ministry of Education, School of Chemistry and Chemical Engineering, Huazhong University of Science and Technology, Wuhan 430074 (China); Wu, Kangbing, E-mail: kbwu@hust.edu.cn [Key Laboratory for Large-Format Battery Materials and System, Ministry of Education, School of Chemistry and Chemical Engineering, Huazhong University of Science and Technology, Wuhan 430074 (China); Wu, Gang [Materials Physics and Applications Division, Los Alamos National Laboratory, Los Alamos, NM 87545 (United States); Li, Qing, E-mail: qing_li_2@brown.edu [Materials Physics and Applications Division, Los Alamos National Laboratory, Los Alamos, NM 87545 (United States)

2014-05-01

Highlights: • Graphene was prepared by one-step solvent exfoliation as superior electrode material. • Compared with RGO, prepared graphene exhibited stronger signal enhancement. • A widespread and highly-sensitive electrochemical sensing platform was constructed. - Abstract: Graphene was easily obtained via one-step ultrasonic exfoliation of graphite powder in N-methyl-2-pyrrolidone. Scanning electron microscopy, transmission electron microscopy, Raman and particle size measurements indicated that the exfoliation efficiency and the amount of produced graphene increased with ultrasonic time. The electrochemical properties and analytical applications of the resulting graphene were systematically studied. Compared with the predominantly-used reduced graphene oxides, the obtained graphene by one-step solvent exfoliation greatly enhanced the oxidation signals of various analytes, such as ascorbic acid (AA), dopamine (DA), uric acid (UA), xanthine (XA), hypoxanthine (HXA), bisphenol A (BPA), ponceau 4R, and sunset yellow. The detection limits of AA, DA, UA, XA, HXA, BPA, ponceau 4R, and sunset yellow were evaluated to be 0.8 μM, 7.5 nM, 2.5 nM, 4 nM, 10 nM, 20 nM, 2 nM, and 1 nM, which are much lower than the reported values. Thus, the prepared graphene via solvent exfoliation strategy displays strong signal amplification ability and holds great promise in constructing a universal and sensitive electrochemical sensing platform.

MicroRNA-143 Activation Regulates Smooth Muscle and Endothelial Cell Crosstalk in Pulmonary Arterial Hypertension.

Science.gov (United States)

Deng, Lin; Blanco, Francisco J; Stevens, Hannah; Lu, Ruifang; Caudrillier, Axelle; McBride, Martin; McClure, John D; Grant, Jenny; Thomas, Matthew; Frid, Maria; Stenmark, Kurt; White, Kevin; Seto, Anita G; Morrell, Nicholas W; Bradshaw, Angela C; MacLean, Margaret R; Baker, Andrew H

2015-10-23

The pathogenesis of pulmonary arterial hypertension (PAH) remains unclear. The 4 microRNAs representing the miR-143 and miR-145 stem loops are genomically clustered. To elucidate the transcriptional regulation of the miR-143/145 cluster and the role of miR-143 in PAH. We identified the promoter region that regulates miR-143/145 microRNA expression in pulmonary artery smooth muscle cells (PASMCs). We mapped PAH-related signaling pathways, including estrogen receptor, liver X factor/retinoic X receptor, transforming growth factor-β (Smads), and hypoxia (hypoxia response element), that regulated levels of all pri-miR stem loop transcription and resulting microRNA expression. We observed that miR-143-3p is selectively upregulated compared with miR-143-5p during PASMC migration. Modulation of miR-143 in PASMCs significantly altered cell migration and apoptosis. In addition, we found high abundance of miR-143-3p in PASMC-derived exosomes. Using assays with pulmonary arterial endothelial cells, we demonstrated a paracrine promigratory and proangiogenic effect of miR-143-3p-enriched exosomes from PASMC. Quantitative polymerase chain reaction and in situ hybridization showed elevated expression of miR-143 in calf models of PAH and in samples from PAH patients. Moreover, in contrast to our previous findings that had not supported a therapeutic role in vivo, we now demonstrate a protective role of miR-143 in experimental pulmonary hypertension in vivo in miR-143-/- and anti-miR-143-3p-treated mice exposed to chronic hypoxia in both preventative and reversal settings. MiR-143-3p modulated both cellular and exosome-mediated responses in pulmonary vascular cells, whereas inhibition of miR-143-3p blocked experimental pulmonary hypertension. Taken together, these findings confirm an important role for the miR-143/145 cluster in PAH pathobiology. © 2015 American Heart Association, Inc.

Scanning laser polarimetry in eyes with exfoliation syndrome.

Science.gov (United States)

Dimopoulos, Antonios T; Katsanos, Andreas; Mikropoulos, Dimitrios G; Giannopoulos, Theodoros; Empeslidis, Theodoros; Teus, Miguel A; Holló, Gábor; Konstas, Anastasios G P

2013-01-01

To compare retinal nerve fiber layer thickness (RNFLT) of normotensive eyes with exfoliation syndrome (XFS) and healthy eyes.
 Sixty-four consecutive individuals with XFS and normal office-time intraocular pressure (IOP) and 72 consecutive healthy controls were prospectively enrolled for a cross-sectional analysis in this hospital-based observational study. The GDx-VCC parameters (temporal-superior-nasal-inferior-temporal [TSNIT] average, superior average, inferior average, TSNIT standard deviation (SD), and nerve fiber indicator [NFI]) were compared between groups. Correlation between various clinical parameters and RNFLT parameters was investigated with Spearman coefficient. 
 The NFI, although within normal limits for both groups, was significantly greater in the XFS group compared to controls: the respective median and interquartile range (IQR) values were 25.1 (22.0-29.0) vs 15.0 (12.0-20.0), ppolarimetry-determined RNFLT was lower in XFS eyes with normal IOP. Therefore, close monitoring of RNFLT may facilitate early identification of those XFS eyes that convert to exfoliative glaucoma.

Isocyanate toughening of pCBT/organoclay nanocomposites with exfoliated structure and enhanced mechanical properties

Directory of Open Access Journals (Sweden)

T. Abt

2014-12-01

Full Text Available Cyclic butylene terephthalate (CBT® is an interesting matrix material for the preparation of nanocomposites due to its very low, water-like melt viscosity which favours clay exfoliation. Nevertheless, polymerized CBT (pCBT is inherently brittle. This paper reports the preparation of isocyanate-toughened nanocomposites made from CBT and organo-modified montmorillonite. The role of the organoclay as reinforcement and the polymeric isocyanate (PMDI as toughening agent on the properties of pCBT was studied. The organoclay increased the stiffness and strength by up to 20% whereas the PMDI improved the deformation behaviour. However, the PMDI did not affect the degree of clay dispersion or exfoliation and flocculated-intercalated structures were observed. The compatibility between the pCBT matrix and clay was further increased by preparing PMDI-tethered intercalated organoclay. The modified organoclay then exfoliated during ring-opening polymerization and yielded true pCBT/clay nanocomposites. This work demonstrates that reactive chain extension of CBT with a polyfunctional isocyanate is an effective method to obtain toughened pCBT nanocomposites. Moreover, isocyanates can enhance the compatibility between pCBT and nanofiller as well as the degree of exfoliation.

Giant Cell Tumor of the Thoracic Spine Presenting as a Posterior Mediastinal Tumor with Benign Pulmonary Metastases: A Case Report

Energy Technology Data Exchange (ETDEWEB)

Kim, Tae Hun [Daegu Fatima Hospital College of Medicine, Daegu (Korea, Republic of); Rho, Byung Hak; Bahn, Young Eun; Choi, Won Il [Dongsan Medical Center, Keimyung University School of Medicine, Daegu (Korea, Republic of)

2010-11-15

Giant cell tumor of bone is a benign, but potentially aggressive lesion that can show local recurrence and metastases. We report here on a case of a 29-year-old man who presented with an incidentally found mediastinal mass. Chest radiography and computed tomography showed a huge mediastinal mass with bilateral pulmonary nodules and the diagnosis of giant cell tumor with benign pulmonary metastasis was confirmed. To the best of our knowledge, this is the first reported case of primary thoracic spinal giant cell tumor manifesting as a huge mediastinal mass with pulmonary metastases

Pulmonary candidiasis after hematopoietic stem cell transplantation: thin-section CT findings.

Science.gov (United States)

Franquet, Tomás; Müller, Nestor L; Lee, Kyung S; Oikonomou, Anastasia; Flint, Julia D

2005-07-01

To retrospectively evaluate thin-section computed tomographic (CT) findings in hematopoietic stem cell transplant (ie, bone marrow transplant) patients with histopathologically proved pulmonary candidiasis. Ethical approval was obtained from the institutional review board of each of the three institutions; informed consent was not required. The study included 17 hematopoietic stem cell transplant recipients with proved pulmonary candidiasis. Histopathologic specimens were acquired at transbronchial biopsy (n = 8), open lung biopsy (n = 6), and autopsy (n = 3). The patients included seven men and 10 women (age range, 20-62 years; mean age, 37 years). The thin-section CT scans were retrospectively reviewed by two thoracic radiologists for the presence, appearance, and distribution of parenchymal abnormalities. Multiple nodules were present in 15 (88%) patients, including centrilobular nodules and tree-in-bud pattern in seven (41%) patients. Nodules were bilateral in 12 patients and unilateral in three. An associated halo of ground-glass opacity was identified in five (33%) patients. Nodules were the only CT finding in five patients (29%). Areas of air-space consolidation were identified in 11 (65%) patients. Areas of ground-glass opacity were seen in six (35%) of 17 patients and were always associated with other abnormalities. Other less common CT findings included pleural effusion (n = 3), thickening of the bronchial walls (n = 2), and cavitation (n = 1). The most common thin-section CT findings of pulmonary candidiasis in hematopoietic stem cell transplant patients are multiple bilateral nodular opacities often associated with areas of consolidation. Copyright RSNA, 2005

Engineering monolayer poration for rapid exfoliation of microbial membranes.

Science.gov (United States)

Pyne, Alice; Pfeil, Marc-Philipp; Bennett, Isabel; Ravi, Jascindra; Iavicoli, Patrizia; Lamarre, Baptiste; Roethke, Anita; Ray, Santanu; Jiang, Haibo; Bella, Angelo; Reisinger, Bernd; Yin, Daniel; Little, Benjamin; Muñoz-García, Juan C; Cerasoli, Eleonora; Judge, Peter J; Faruqui, Nilofar; Calzolai, Luigi; Henrion, Andre; Martyna, Glenn J; Grovenor, Chris R M; Crain, Jason; Hoogenboom, Bart W; Watts, Anthony; Ryadnov, Maxim G

2017-02-01

The spread of bacterial resistance to traditional antibiotics continues to stimulate the search for alternative antimicrobial strategies. All forms of life, from bacteria to humans, are postulated to rely on a fundamental host defense mechanism, which exploits the formation of open pores in microbial phospholipid bilayers. Here we predict that transmembrane poration is not necessary for antimicrobial activity and reveal a distinct poration mechanism that targets the outer leaflet of phospholipid bilayers. Using a combination of molecular-scale and real-time imaging, spectroscopy and spectrometry approaches, we introduce a structural motif with a universal insertion mode in reconstituted membranes and live bacteria. We demonstrate that this motif rapidly assembles into monolayer pits that coalesce during progressive membrane exfoliation, leading to bacterial cell death within minutes. The findings offer a new physical basis for designing effective antibiotics.

Properties of spray-deposited liquid-phase exfoliated graphene films

Science.gov (United States)

Sales, Maria Gabriela C.; Dela Vega, Ma. Shanlene D. C.; Vasquez, Magdaleno R., Jr.

2018-01-01

In this study, we demonstrate the feasibility of spray-depositing exfoliated graphene on flexible polyimide (PI) and rigid (soda lime glass) substrates for optoelectronic applications. The water contact angles of the substrates increased by 13% (for PI) and 49% (for glass) when the surfaces are pretreated with hexamethyldisiloxane, which significantly improved the adhesion of the films. Raman spectral analyses confirmed a minimum of 15 and a maximum of 23 layers of exfoliated graphene deposited on the substrates. After deposition, the films were exposed to 13.56 MHz radio-frequency plasma containing an admixture of argon and nitrogen gases. Plasma treatment modified the electrical properties with a response analogous to that of a rectifier. A 39% increase in transmittance in the visible region was also observed especially for glass substrates after plasma treatment without a significant change in film electrical conductivity.

Exfoliation of graphite into graphene in aqueous solutions of inorganic salts.

Science.gov (United States)

Parvez, Khaled; Wu, Zhong-Shuai; Li, Rongjin; Liu, Xianjie; Graf, Robert; Feng, Xinliang; Müllen, Klaus

2014-04-23

Mass production of high-quality graphene sheets is essential for their practical application in electronics, optoelectronics, composite materials, and energy-storage devices. Here we report a prompt electrochemical exfoliation of graphene sheets into aqueous solutions of different inorganic salts ((NH4)2SO4, Na2SO4, K2SO4, etc.). Exfoliation in these electrolytes leads to graphene with a high yield (>85%, ≤3 layers), large lateral size (up to 44 μm), low oxidation degree (a C/O ratio of 17.2), and a remarkable hole mobility of 310 cm(2) V(-1) s(-1). Further, highly conductive graphene films (11 Ω sq(-1)) are readily fabricated on an A4-size paper by applying brush painting of a concentrated graphene ink (10 mg mL(-1), in N,N'-dimethylformamide). All-solid-state flexible supercapacitors manufactured on the basis of such graphene films deliver a high area capacitance of 11.3 mF cm(-2) and an excellent rate capability of 5000 mV s(-1). The described electrochemical exfoliation shows great promise for the industrial-scale synthesis of high-quality graphene for numerous advanced applications.

Nuclear scan of pulmonary hemorrhage in radiopathic pulmonary hemosiderosis

International Nuclear Information System (INIS)

Miller, T.; Tanaka, T.

1979-01-01

Idiopathic pulmonary hemosiderosis, a disease of unknown etiology most often occuring in children, is characterized by recurring episodes of alveolar consolidation. Exacerbations of pulmonary hemorrhage coincide with episodes of alveolar filling; repeated episodes lead to progressive interstitial fibrosis and eventually to corpulmonale. Serial nuclear scans of the lungs after injection of radiolabeled red blood cells should parallel the pathologic and radiographic findings. We observed the accumulation of radiolabeled red blood cells in the lungs on scan images, a finding not previously reported

Synthesis, characterization and photocatalytic performance of chemically exfoliated MoS2

Science.gov (United States)

Prabhakar Vattikuti, S. V.; Shim, Jaesool

2018-03-01

Two-dimensional (2D) layered structure transition metal dichalcogenides (TMDs) has gained huge attention and importance for photocatalytic energy conversion because of their unique properties. Molybdenum disulfide (MoS2) nanosheets were synthesized via one-pot method and exfoliated in (dimethylformamide) DMF solution. Subsequent exfoliated MoS2 nanosheets (e-MoS2) were used as photocatalysts for degradation of Rhodamine B (RhB) pollutant under solar light irradiation. The e-MoS2 nanosheets exhibited excellent photocatalytic activity than that of pristine MoS2, owing to high specific surface area with enormous active sites and light absorption capacity. In addition, e-MoS2 demonstrated remarkable photocatalytic stability.

A case of acute exacerbation of idiopathic pulmonary fibrosis after proton beam therapy for non-small cell lung cancer

International Nuclear Information System (INIS)

Nagano, Tatsuya; Kotani, Yoshikazu; Fujii, Osamu

2012-01-01

There have been no reports describing acute exacerbations of idiopathic pulmonary fibrosis after particle radiotherapy for non-small cell lung cancer. The present study describes the case of a 76-year-old Japanese man with squamous cell carcinoma of the lung that relapsed in the left upper lobe 1 year after right upper lobectomy. He had been treated with oral prednisolone 20 mg/day every 2 days for idiopathic pulmonary fibrosis, and the relapsed lung cancer was treated by proton beam therapy, which was expected to cause the least adverse effects on the idiopathic pulmonary fibrosis. Fifteen days after the initiation of proton beam therapy, the idiopathic pulmonary fibrosis exacerbated, centered on the left upper lobe, for which intensive steroid therapy was given. About 3 months later, the acute exacerbation of idiopathic pulmonary fibrosis had improved, and the relapsed lung cancer became undetectable. Clinicians should be aware that an acute exacerbation of idiopathic pulmonary fibrosis may occur even in proton beam therapy, although proton beam therapy appears to be an effective treatment option for patients with idiopathic pulmonary fibrosis. (author)

Morphological, viscoelastic and mechanical characterization of polypropylene/exfoliated graphite nanocomposites

Directory of Open Access Journals (Sweden)

Creusa Iara Ferreira

2013-01-01

Full Text Available The viscoelastic, mechanical and morphological properties of polypropylene/exfoliated graphite nanocomposites with different contents of nanofiller were investigated. According to transmission electron microscopy results, the nanofiller particles were homogeneously dispersed in the matrix. The rheological properties indicated that incorporation of graphite improved the matrix stiffness and had a reinforcing effect. Exfoliated graphite had a weak interaction with the polypropylene. The behavior of the nanocomposites was similar to that of polypropylene in terms of the interfacial detachment inferred from the transmission electron microscopy images and of their G' (storage and G'' (loss moduli, and viscosity. The mechanical properties of the nanocomposites compared to the matrix improved significantly for the flexural and storage moduli with little loss of impact strength.

Morphological, viscoelastic and mechanical characterization of polypropylene/exfoliated graphite nanocomposites

Energy Technology Data Exchange (ETDEWEB)

Ferreira, Creusa Iara; Oliveira, Ricardo Vinicius Bof de; Mauler, Raquel Santos, E-mail: raquel.mauler@ufrgs.br [Universidade Federal do Rio Grande do Sul (PGCIMAT/IQ/UFRGS), Porto Alegre, RS (Brazil); Bianchi, Otavio [Universidade de Caxias do Sul (PGMAT/CCET/UCS), RS (Brazil); Oviedo, Mauro Alfredo Soto [Braskem S/A, Rio de Janeiro, RJ (Brazil)

2013-07-01

The viscoelastic, mechanical and morphological properties of polypropylene/exfoliated graphite nanocomposites with different contents of nanofiller were investigated. According to transmission electron microscopy results, the nanofiller particles were homogeneously dispersed in the matrix. The rheological properties indicated that incorporation of graphite improved the matrix stiffness and had a reinforcing effect. Exfoliated graphite had a weak interaction with the polypropylene. The behavior of the nanocomposites was similar to that of polypropylene in terms of the interfacial detachment inferred from the transmission electron microscopy images and of their G' (storage) and G' (loss) moduli, and viscosity. The mechanical properties of the nanocomposites compared to the matrix improved significantly for the flexural and storage moduli with little loss of impact strength. (author)

Surgical treatment in non-small cell lung cancer with pulmonary oligometastasis.

Science.gov (United States)

He, Jinyuan; Li, Yun; An, Jun; Hu, Liu; Zhang, Junhang

2017-02-02

Previous studies have demonstrated survival benefits for local treatment in solitary metastatic non-small cell lung cancer (NSCLC).This study aimed to investigate the effect of local surgery for NSCLC with pulmonary oligometastasis. This study included 21 patients of NSCLC with pulmonary oligometastasis between January 2003 and December 2013, which were divided into two groups, group A (11 cases) for local surgery and group B (10 cases) for systematic chemotherapy, compared the median survival time (MST) and 5-year survival rate between the two groups, and analyzed the impact of the pathological types, the TNM and pN stage of primary tumor, the site, and the mode and number of oligometastatic nodule on group A. The MST of group A and B were 37 and 11.6 months respectively, 5-year survival rates were 18.2 and 9.1% respectively (p  0.05). Local surgery significantly prolonged the overall survival time and 5-year survival rate of primary NSCLC with pulmonary oligometastasis.

Engraftment of Bone Marrow Progenitor Cells in a Rat Model of Asbestos-Induced Pulmonary Fibrosis

OpenAIRE

Spees, Jeffrey L.; Pociask, Derek A.; Sullivan, Deborah E.; Whitney, Mandolin J.; Lasky, Joseph A.; Prockop, Darwin J.; Brody, Arnold R.

2007-01-01

Rationale: Bone marrow–derived cells have been shown to engraft during lung fibrosis. However, it is not known if similar cells engraft consequent to inhalation of asbestos fibers that cause pulmonary fibrosis, or if the cells proliferate and differentiate at sites of injury.

Pulmonary function in children and adolescents with sickle cell disease: have we paid proper attention to this problem?

Directory of Open Access Journals (Sweden)

Ana Karine Vieira

Full Text Available ABSTRACT Objective: To evaluate pulmonary function and functional capacity in children and adolescents with sickle cell disease. Methods: This was a cross-sectional study involving 70 children and adolescents (8-15 years of age with sickle cell disease who underwent pulmonary function tests (spirometry and functional capacity testing (six-minute walk test. The results of the pulmonary function tests were compared with variables related to the severity of sickle cell disease and history of asthma and of acute chest syndrome. Results: Of the 64 patients who underwent spirometry, 15 (23.4% showed abnormal results: restrictive lung disease, in 8 (12.5%; and obstructive lung disease, in 7 (10.9%. Of the 69 patients who underwent the six-minute walk test, 18 (26.1% showed abnormal results regarding the six-minute walk distance as a percentage of the predicted value for age, and there was a ≥ 3% decrease in SpO2 in 36 patients (52.2%. Abnormal pulmonary function was not significantly associated with any of the other variables studied, except for hypoxemia and restrictive lung disease. Conclusions: In this sample of children and adolescents with sickle cell disease, there was a significant prevalence of abnormal pulmonary function. The high prevalence of respiratory disorders suggests the need for a closer look at the lung function of this population, in childhood and thereafter.

Efficacy and safety of regenerative cell therapy for pulmonary arterial hypertension in animal models: a preclinical systematic review protocol.

Science.gov (United States)

Suen, Colin M; Zhai, Alex; Lalu, Manoj M; Welsh, Christopher; Levac, Brendan M; Fergusson, Dean; McIntyre, Lauralyn; Stewart, Duncan J

2016-05-25

Pulmonary arterial hypertension (PAH) is a rare disease (15 cases per million) that is characterized by widespread loss of the pulmonary microcirculation and elevated pulmonary vascular resistance leading to pathological right ventricular remodeling and ultimately right heart failure. Regenerative cell therapies (i.e., therapies involving cells with stem or progenitor-like properties) could potentially restore the effective lung microcirculation and provide a curative therapy for PAH. Preclinical evidence suggests that regenerative cell therapy using endothelial progenitor cells or mesenchymal stem cells may be beneficial in the treatment of PAH. These findings have led to the completion of a small number of human clinical trials, albeit with modest effect compared to animal studies. The objective of this systematic review is to compare the efficacy and safety of regenerative cell therapies in preclinical models of PAH as well as assess study quality to inform future clinical studies. We will include preclinical studies of PAH in which a regenerative cell type was administered and outcomes compared to a disease control. The primary outcome will be pulmonary hemodynamics as assessed by measurement of right ventricular systolic pressure and/or mean pulmonary arterial pressure. Secondary outcomes will include mortality, survival, right ventricular remodeling, pulmonary vascular resistance, cardiac output, cardiac index, pulmonary acceleration time, tricuspid annular systolic excursion, and right ventricular wall thickness. Electronic searches of MEDLINE and EMBASE databases will be constructed and reviewed by the Peer Review of Electronic Search Strategies (PRESS) process. Search results will be screened independently in duplicate. Data from eligible studies will be extracted, pooled, and analyzed using random effects models. Risk of bias will be assessed using the SYstematic Review Centre for Laboratory animal Experimentation (SYRCLE) risk of bias tool, and

Dynamic and diverse changes in the functional properties of vascular smooth muscle cells in pulmonary hypertension.

Science.gov (United States)

Stenmark, Kurt R; Frid, Maria G; Graham, Brian B; Tuder, Rubin M

2018-03-15

Pulmonary hypertension (PH) is the end result of interaction between pulmonary vascular tone and a complex series of cellular and molecular events termed 'vascular remodelling'. The remodelling process, which can involve the entirety of pulmonary arterial vasculature, almost universally involves medial thickening, driven by increased numbers and hypertrophy of its principal cellular constituent, smooth muscle cells (SMCs). It is noted, however that SMCs comprise heterogeneous populations of cells, which can exhibit markedly different proliferative, inflammatory, and extracellular matrix production changes during remodelling. We further consider that these functional changes in SMCs of different phenotype and their role in PH are dynamic and may undergo significant changes over time (which we will refer to as cellular plasticity); no single property can account for the complexity of the contribution of SMC to pulmonary vascular remodelling. Thus, the approaches used to pharmacologically manipulate PH by targeting the SMC phenotype(s) must take into account processes that underlie dominant phenotypes that drive the disease. We present evidence for time- and location-specific changes in SMC proliferation in various animal models of PH; we highlight the transient nature (rather than continuous) of SMC proliferation, emphasizing that the heterogenic SMC populations that reside in different locations along the pulmonary vascular tree exhibit distinct responses to the stresses associated with the development of PH. We also consider that cells that have often been termed 'SMCs' may arise from many origins, including endothelial cells, fibroblasts and resident or circulating progenitors, and thus may contribute via distinct signalling pathways to the remodelling process. Ultimately, PH is characterized by long-lived, apoptosis-resistant SMC. In line with this key pathogenic characteristic, we address the acquisition of a pro-inflammatory phenotype by SMC that is essential

Pinocembrin ex vivo preconditioning improves the therapeutic efficacy of endothelial progenitor cells in monocrotaline-induced pulmonary hypertension in rats.

Science.gov (United States)

Ahmed, Lamiaa A; Rizk, Sherine M; El-Maraghy, Shohda A

2017-08-15

Pulmonary hypertension is still not curable and the available current therapies can only alleviate symptoms without hindering the progression of disease. The present study was directed to investigate the possible modulatory effect of pinocembrin on endothelial progenitor cells transplanted in monocrotaline-induced pulmonary hypertension in rats. Pulmonary hypertension was induced by a single subcutaneous injection of monocrotaline (60mg/kg). Endothelial progenitor cells were in vitro preconditioned with pinocembrin (25mg/L) for 30min before being i.v. injected into rats 2weeks after monocrotaline administration. Four weeks after monocrotaline administration, blood pressure, electrocardiography and right ventricular systolic pressure were recorded. Rats were sacrificed and serum was separated for determination of endothelin-1 and asymmetric dimethylarginine levels. Right ventricles and lungs were isolated for estimation of tumor necrosis factor-alpha and transforming growth factor-beta contents as well as caspase-3 activity. Moreover, protein expression of matrix metalloproteinase-9 and endothelial nitric oxide synthase in addition to myocardial connexin-43 was assessed. Finally, histological analysis of pulmonary arteries, cardiomyocyte cross-sectional area and right ventricular hypertrophy was performed and cryosections were done for estimation of cell homing. Preconditioning with pinocembrin provided a significant improvement in endothelial progenitor cells' effect towards reducing monocrotaline-induced elevation of inflammatory, fibrogenic and apoptotic markers. Furthermore, preconditioned cells induced a significant amelioration of endothelial markers and cell homing and prevented monocrotaline-induced changes in right ventricular function and histological analysis compared with native cells alone. In conclusion, pinocembrin significantly improves the therapeutic efficacy of endothelial progenitor cells in monocrotaline-induced pulmonary hypertension in rats

Clinical characteristics and computed tomography findings of pulmonary toxoplasmosis after hematopoietic stem cell transplantation.

Science.gov (United States)

Sumi, Masahiko; Norose, Kazumi; Hikosaka, Kenji; Kaiume, Hiroko; Takeda, Wataru; Kirihara, Takehiko; Kurihara, Taro; Sato, Keijiro; Ueki, Toshimitsu; Hiroshima, Yuki; Kuraishi, Hiroshi; Watanabe, Masahide; Kobayashi, Hikaru

2016-12-01

The prognosis of pulmonary toxoplasmosis, including disseminated toxoplasmosis involving the lungs, following hematopoietic stem cell transplantation (HSCT) is extremely poor due to the difficulties associated with early diagnosis and the rapidly progressive deterioration of multiorgan function. In our institution, we identified nine cases of toxoplasmosis, representing incidences of 2.2 and 19.6 % among all HSCT recipients and seropositive HSCT recipients, respectively. Of the patients with toxoplasmosis, six had pulmonary toxoplasmosis. Chest computed tomography (CT) findings revealed centrilobular, patchy ground-glass opacities (n = 3), diffuse ground-glass opacities (n = 2), ground-glass opacities with septal thickening (n = 1), and marked pleural effusion (n = 1). All cases died, except for one with suspected pulmonary toxoplasmosis who was diagnosed by a polymerase chain reaction assay 2 days after the onset of symptoms. In pulmonary toxoplasmosis, CT findings are non-specific and may mimic pulmonary congestion, atypical pneumonia, viral pneumonitis, and bronchopneumonia. Early diagnosis and treatment is crucial for overcoming this serious infectious complication. Pulmonary toxoplasmosis should be considered during differential diagnosis in a recipient with otherwise unexplained signs of infection and CT findings with ground-glass opacities, regardless of the distribution.

Pre-cancer risk assessment in habitual smokers from DIC images of oral exfoliative cells using active contour and SVM analysis.

Science.gov (United States)

Dey, Susmita; Sarkar, Ripon; Chatterjee, Kabita; Datta, Pallab; Barui, Ananya; Maity, Santi P

2017-04-01

Habitual smokers are known to be at higher risk for developing oral cancer, which is increasing at an alarming rate globally. Conventionally, oral cancer is associated with high mortality rates, although recent reports show the improved survival outcomes by early diagnosis of disease. An effective prediction system which will enable to identify the probability of cancer development amongst the habitual smokers, is thus expected to benefit sizable number of populations. Present work describes a non-invasive, integrated method for early detection of cellular abnormalities based on analysis of different cyto-morphological features of exfoliative oral epithelial cells. Differential interference contrast (DIC) microscopy provides a potential optical tool as this mode provides a pseudo three dimensional (3-D) image with detailed morphological and textural features obtained from noninvasive, label free epithelial cells. For segmentation of DIC images, gradient vector flow snake model active contour process has been adopted. To evaluate cellular abnormalities amongst habitual smokers, the selected morphological and textural features of epithelial cells are compared with the non-smoker (-ve control group) group and clinically diagnosed pre-cancer patients (+ve control group) using support vector machine (SVM) classifier. Accuracy of the developed SVM based classification has been found to be 86% with 80% sensitivity and 89% specificity in classifying the features from the volunteers having smoking habit. Copyright © 2017 Elsevier Ltd. All rights reserved.

Urea-assisted liquid-phase exfoliation of natural graphite into few-layer graphene

Science.gov (United States)

Hou, Dandan; Liu, Qinfu; Wang, Xianshuai; Qiao, Zhichuan; Wu, Yingke; Xu, Bohui; Ding, Shuli

2018-05-01

The mass production of graphene with high quality is desirable for its wide applications. Here, we demonstrated a facile method to exfoliate natural graphite into graphene in organic solvent by assisting of urea. The exfoliation of graphite may originate from the "molecular wedge" effect of urea, which can intercalate into the edge of natural graphite, thus facilitating the production of graphene dispersion with a high concentration up to 1.2 mg/mL. The obtained graphene is non-oxidized with negligible defects. Therefore, this approach has great promise in bulk production of graphene with superior quality for a variety of applications.

Evaluation of the capacity of heavy metal adsorption in exfoliated vermiculite

International Nuclear Information System (INIS)

Lima, J.F.; Silva, P.S.; Hanken, R.B.L.; Raposo, C.M.O.

2009-01-01

Many groups from modern society have seen with attention the issues of pollutants, generally present in nature, those same that have caused irreversible damages to the environment. The Vermiculite, a phyllosilicate, with t-o-t structure, have high interlamelar charge, has been studied as cationic exchanger, whose application when exfoliated, are increased. This work has the objective of evaluate the absorption capacity of chromium (III), in different concentrations, in high, slim and medium concentrations of exfoliated vermiculites. The results obtained from the characterization by spectroscopy in infrared and by diffraction of x-ray from prepared solids showed important variations in the quantity of adsorbed metal in order the size of the concentrated particles. (author)

An Immature Myeloid/Myeloid-Suppressor Cell Response Associated with Necrotizing Inflammation Mediates Lethal Pulmonary Tularemia.

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Sivakumar Periasamy

2016-03-01

Full Text Available Inhalation of Francisella tularensis (Ft causes acute and fatal pneumonia. The lung cytokine milieu favors exponential Ft replication, but the mechanisms underlying acute pathogenesis and death remain unknown. Evaluation of the sequential and systemic host immune response in pulmonary tularemia reveals that in contrast to overwhelming bacterial burden or cytokine production, an overt innate cellular response to Ft drives tissue pathology and host mortality. Lethal infection with Ft elicits medullary and extra-medullary myelopoiesis supporting recruitment of large numbers of immature myeloid cells and MDSC to the lungs. These cells fail to mature and die, leading to subsequent necrotic lung damage, loss of pulmonary function, and host death that is partially dependent upon immature Ly6G+ cells. Acceleration of this process may account for the rapid lethality seen with Ft SchuS4. In contrast, during sub-lethal infection with Ft LVS the pulmonary cellular response is characterized by a predominance of mature neutrophils and monocytes required for protection, suggesting a required threshold for lethal bacterial infection. Further, eliciting a mature phagocyte response provides transient, but dramatic, innate protection against Ft SchuS4. This study reveals that the nature of the myeloid cell response may be the primary determinant of host mortality versus survival following Francisella infection.

An Immature Myeloid/Myeloid-Suppressor Cell Response Associated with Necrotizing Inflammation Mediates Lethal Pulmonary Tularemia

Science.gov (United States)

Periasamy, Sivakumar; Avram, Dorina; McCabe, Amanda; MacNamara, Katherine C.; Sellati, Timothy J.; Harton, Jonathan A.

2016-01-01

Inhalation of Francisella tularensis (Ft) causes acute and fatal pneumonia. The lung cytokine milieu favors exponential Ft replication, but the mechanisms underlying acute pathogenesis and death remain unknown. Evaluation of the sequential and systemic host immune response in pulmonary tularemia reveals that in contrast to overwhelming bacterial burden or cytokine production, an overt innate cellular response to Ft drives tissue pathology and host mortality. Lethal infection with Ft elicits medullary and extra-medullary myelopoiesis supporting recruitment of large numbers of immature myeloid cells and MDSC to the lungs. These cells fail to mature and die, leading to subsequent necrotic lung damage, loss of pulmonary function, and host death that is partially dependent upon immature Ly6G+ cells. Acceleration of this process may account for the rapid lethality seen with Ft SchuS4. In contrast, during sub-lethal infection with Ft LVS the pulmonary cellular response is characterized by a predominance of mature neutrophils and monocytes required for protection, suggesting a required threshold for lethal bacterial infection. Further, eliciting a mature phagocyte response provides transient, but dramatic, innate protection against Ft SchuS4. This study reveals that the nature of the myeloid cell response may be the primary determinant of host mortality versus survival following Francisella infection. PMID:27015566

Thrombin has biphasic effects on the nitric oxide-cGMP pathway in endothelial cells and contributes to experimental pulmonary hypertension.

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Katrin F Nickel

Full Text Available BACKGROUND: A potential role for coagulation factors in pulmonary arterial hypertension has been recently described, but the mechanism of action is currently not known. Here, we investigated the interactions between thrombin and the nitric oxide-cGMP pathway in pulmonary endothelial cells and experimental pulmonary hypertension. PRINCIPAL FINDINGS: Chronic treatment with the selective thrombin inhibitor melagatran (0.9 mg/kg daily via implanted minipumps reduced right ventricular hypertrophy in the rat monocrotaline model of experimental pulmonary hypertension. In vitro, thrombin was found to have biphasic effects on key regulators of the nitric oxide-cGMP pathway in endothelial cells (HUVECs. Acute thrombin stimulation led to increased expression of the cGMP-elevating factors endothelial nitric oxide synthase (eNOS and soluble guanylate cyclase (sGC subunits, leading to increased cGMP levels. By contrast, prolonged exposition of pulmonary endothelial cells to thrombin revealed a characteristic pattern of differential expression of the key regulators of the nitric oxide-cGMP pathway, in which specifically the factors contributing to cGMP elevation (eNOS and sGC were reduced and the cGMP-hydrolyzing PDE5 was elevated (qPCR and Western blot. In line with the differential expression of key regulators of the nitric oxide-cGMP pathway, a reduction of cGMP by prolonged thrombin stimulation was found. The effects of prolonged thrombin exposure were confirmed in endothelial cells of pulmonary origin (HPAECs and HPMECs. Similar effects could be induced by activation of protease-activated receptor-1 (PAR-1. CONCLUSION: These findings suggest a link between thrombin generation and cGMP depletion in lung endothelial cells through negative regulation of the nitric oxide-cGMP pathway, possibly mediated via PAR-1, which could be of relevance in pulmonary arterial hypertension.

Exfoliative Dermatitis Due To Carbamazepine In An Epileptic Patient

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Ghosh Sadhan Kr

1995-01-01

Full Text Available A young epileptic girl of 17 years who was being treated with carbamazepine suddenly developed exanthematous skin eruption all over the body resulting in exfoliative dermatitis within 2 days of onset. The drug was withdrawn and the patient responded well with symptomatic treatment.

Congenital adrenal hyperplasia: a case report with premature teeth exfoliation and bone resorption.

Science.gov (United States)

Angelopoulou, Matina V; Kontogiorgos, Elias; Emmanouil, Dimitris

2015-06-01

Congenital adrenal hyperplasia (CAH) is an inherited autosomal recessive disorder characterized by insufficient production of cortisol. The aim of this case report was to present a child with CAH, premature exfoliation of primary teeth and accelerated eruption of his permanent teeth related to bone resorption. A 4.5-year-old Caucasian boy with CAH and long-term administration of glucocorticoids was referred for dental restoration. Clinical examination revealed primary molars with worn stainless steel crowns, severe attrition of the upper canines, and absence of the upper incisors. Before the completion of treatment, abnormal mobility of the first upper primary molars and the lower incisors was detected, and a few days later the teeth exfoliated prematurely. Histologic examination revealed normal tooth structure. Alkaline phosphatase and blood cells values were normal. Eruption of the permanent dentition was also accelerated. Tooth mobility was noticed in the permanent teeth as soon as they erupted, along with bone destruction. Examination revealed an elevated level of receptor activator of nuclear factor-κB ligand and lower-than-normal osteoprotegerin and vitamin D levels. The patient was treated with vitamin D supplements, and his teeth have been stable ever since. CAH is a serious chronic disorder appearing in children with accelerated dental development and possibly premature loss of primary teeth. Copyright © 2015 by the American Academy of Pediatrics.

Persistent pulmonary interstitial emphysema in a case of Langerhans cell histiocytosis

International Nuclear Information System (INIS)

Abbey, Pooja; Narula, Mahender K.; Anand, Rama; Chandra, Jagdish

2014-01-01

We present the case of a 10-month-old boy with multisystem Langerhans cell histiocytosis showing thin-walled lung cysts along with computed tomography (CT) evidence of persistent pulmonary interstitial emphysema (PPIE), in the absence of pneumothorax or pneumomediastinum. Follow-up CT performed after 6 months demonstrated complete resolution of interstitial emphysema

Doppler-Defined Pulmonary Hypertension in Sickle Cell Anemia in Kurdistan, Iraq.

Science.gov (United States)

Al-Allawi, Nasir; Mohammad, Ameen M; Jamal, Shakir

2016-01-01

To determine the frequency, clinical and laboratory associations of pulmonary hypertension in Iraqi Kurds with sickle cell anemia, a total of ninety four such patients attending a major hemoglobinopathy center in Iraqi Kurdistan were enrolled. All patients were re-evaluated clinically and had their blood counts, HbF, serum ferritin, LDH, renal and liver function assessed. Transthoracic Doppler echocardiography with measurement of tricuspid valve regurgitant jet velocity (TRV) was performed. A TRV in excess of 2.8 m/s was considered for the purposes of this study as indicative of pulmonary hypertension (PH). The prevalence of TRV in excess of 2.8m/s was 10.6%. By univariate analysis: significantly higher reticulocyte count, more frequent blood transfusions and pain episodes were encountered in the PH group as compared to the non-PH group (p = 0.001, 0.045 and 0.02 respectively). Moreover, PH patients had significantly higher mean right atrial area, left atrial size, E wave/A wave ratio and ejection fraction by echocardiography (p = 0.027, 0.037, <0.001 and 0.008 respectively). Except for reticulocyte count none of the other parameters remained significant by multivariate analysis (p = 0.024). In conclusion the current study revealed that pulmonary hypertension is rather frequent among Iraqi Kurds with sickle cell anemia, and identified reticulocyte count as an independently associated parameter with PH in this population. Future prospective studies including right heart catheterization and appropriate medical intervention are warranted.

Interleukin-22 Inhibits Bleomycin-Induced Pulmonary Fibrosis

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Minrui Liang

2013-01-01

Full Text Available Pulmonary fibrosis is a progressive and fatal fibrotic disease of the lungs with unclear etiology. Recent insight has suggested that early injury/inflammation of alveolar epithelial cells could lead to dysregulation of tissue repair driven by multiple cytokines. Although dysregulation of interleukin- (IL- 22 is involved in various pulmonary pathophysiological processes, the role of IL-22 in fibrotic lung diseases is still unclear and needs to be further addressed. Here we investigated the effect of IL-22 on alveolar epithelial cells in the bleomycin- (BLM- induced pulmonary fibrosis. BLM-treated mice showed significantly decreased level of IL-22 in the lung. IL-22 produced γδT cells were also decreased significantly both in the tissues of lungs and spleens. Administration of recombinant human IL-22 to alveolar epithelial cell line A549 cells ameliorated epithelial to mesenchymal transition (EMT and partially reversed the impaired cell viability induced by BLM. Furthermore, blockage of IL-22 deteriorated pulmonary fibrosis, with elevated EMT marker (α-smooth muscle actin (α-SMA and overactivated Smad2. Our results indicate that IL-22 may play a protective role in the development of BLM-induced pulmonary fibrosis and may suggest IL-22 as a novel immunotherapy tool in treating pulmonary fibrosis.

Pulmonary tumors induced in the rat by the internal α irradiation; target cells and sensitive cells

International Nuclear Information System (INIS)

Fritsch, P.; Masse, R.; Nolibe, D.; Metivier, H.; Morin, M.; Lafuma, J.

1977-01-01

Over, 500 rat pulmonary tumors induced by inhalation of various radionuclides have been examined by means of the usual histological methods and ultrastructurally for part of them. Tumor grafts were obtained and several lines have been preserved for several years. The malignity of some varieties: circumscribed epidermoid carcinoma, fibrosarcoma derived from stromareaction, bronchiolo alveolar carcinoma was thus established. It was not possible to establish any relation between the turnover per day and the incidence of pulmonary tumors whatever the correction factor applied taking account of the distribution of the delivered dose. The possibility of showing unapparent lesions of the target cells by grafts of immunodepressed animals suggested that local regulating mechanisms are of particular significance [fr

Induced pluripotent stem cells inhibit bleomycin-induced pulmonary fibrosis in mice through suppressing TGF-β1/Smad-mediated epithelial to mesenchymal transition

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Yan Zhou

2016-11-01

Full Text Available Pulmonary fibrosis is a progressive and irreversible fibrotic lung disorder with high mortality and few treatment options. Recently, induced pluripotent stem (iPS cells have been considered as an ideal resource for stem cell-based therapy. Although an earlier study demonstrated the therapeutic effect of iPS cells on pulmonary fibrosis, the exact mechanisms remain obscure. The present study investigated the effects of iPS cells on inflammatory responses, transforming growth factor (TGF-β1 signaling pathway, and epithelial to mesenchymal transition (EMT during bleomycin (BLM-induced lung fibrosis. A single intratracheal instillation of BLM (5 mg/kg was performed to induce pulmonary fibrosis in C57BL/6 mice. Then, iPS cells (c-Myc-free were administrated intravenously at 24 h following BLM instillation. Three weeks after BLM administration, pulmonary fibrosis was evaluated. As expected, treatment with iPS cells significantly limited the pathological changes, edema, and collagen deposition in lung tissues of BLM-induced mice. Mechanically, treatment with iPS cells obviously repressed the expression ratios of matrix metalloproteinase-2 (MMP-2 to its tissue inhibitor -2 (TIMP-2 and MMP-9/TIMP-1 in BLM-induced pulmonary tissues. In addition, iPS cell administration remarkably suppressed BLM-induced up-regulation of pulmonary inflammatory mediators, including tumor necrosis factor-α, interleukin (IL-1β, IL-6, inducible nitric oxide synthase, nitric oxide, cyclooxygenase-2 and prostaglandin E2. We further demonstrated that transplantation of iPS cells markedly inhibited BLM-mediated activation of TGF-β1/Mothers against decapentaplegic homolog 2/3 (Smad2/3 and EMT in lung tissues through up-regulating epithelial marker E-cadherin and down-regulating mesenchymal markers including fibronectin, vimentin and α-smooth muscle actin. Moreover, in vitro, iPS cell-conditioned medium (iPSC-CM profoundly inhibited TGF-β1-induced EMT signaling pathway in mouse

Exfoliation of the tungsten fibreform nanostructure by unipolar arcing in the LHD divertor plasma

Science.gov (United States)

Tokitani, M.; Kajita, S.; Masuzaki, S.; Hirahata, Y.; Ohno, N.; Tanabe, T.; LHD Experiment Group

2011-10-01

The tungsten nanostructure (W-fuzz) created in the linear divertor simulator (NAGDIS) was exposed to the Large Helical Device (LHD) divertor plasma for only 2 s (1 shot) to study exfoliation/erosion and microscopic modifications due to the high heat/particle loading under high magnetic field conditions. Very fine and randomly moved unipolar arc trails were clearly observed on about half of the W-fuzz area (6 × 10 mm2). The fuzzy surface was exfoliated by continuously moving arc spots even for the very short exposure time. This is the first observation of unipolar arcing and exfoliation of some areas of the W-fuzz structure itself in a large plasma confinement device with a high magnetic field. The typical width and depth of each arc trail were about 8 µm and 1 µm, respectively, and the arc spots moved randomly on the micrometre scale. The fractality of the arc trails was analysed using a box-counting method, and the fractal dimension (D) of the arc trails was estimated to be D ≈ 1.922. This value indicated that the arc spots moved in Brownian motion, and were scarcely influenced by the magnetic field. One should note that such a large scale exfoliation due to unipolar arcing may enhance the surface erosion of the tungsten armour and act as a serious impurity source for fusion plasmas.

Exfoliation of the tungsten fibreform nanostructure by unipolar arcing in the LHD divertor plasma

International Nuclear Information System (INIS)

Tokitani, M.; Masuzaki, S.; Kajita, S.; Hirahata, Y.; Ohno, N.; Tanabe, T.

2011-01-01

The tungsten nanostructure (W-fuzz) created in the linear divertor simulator (NAGDIS) was exposed to the Large Helical Device (LHD) divertor plasma for only 2 s (1 shot) to study exfoliation/erosion and microscopic modifications due to the high heat/particle loading under high magnetic field conditions. Very fine and randomly moved unipolar arc trails were clearly observed on about half of the W-fuzz area (6 x 10 mm 2 ). The fuzzy surface was exfoliated by continuously moving arc spots even for the very short exposure time. This is the first observation of unipolar arcing and exfoliation of some areas of the W-fuzz structure itself in a large plasma confinement device with a high magnetic field. The typical width and depth of each arc trail were about 8 μm and 1 μm, respectively, and the arc spots moved randomly on the micrometre scale. The fractality of the arc trails was analysed using a box-counting method, and the fractal dimension (D) of the arc trails was estimated to be D ∼ 1.922. This value indicated that the arc spots moved in Brownian motion, and were scarcely influenced by the magnetic field. One should note that such a large scale exfoliation due to unipolar arcing may enhance the surface erosion of the tungsten armour and act as a serious impurity source for fusion plasmas. (letter)

Cellular, pharmacological, and biophysical evaluation of explanted lungs from a patient with sickle cell disease and severe pulmonary arterial hypertension.

Science.gov (United States)

Rogers, Natasha M; Yao, Mingyi; Sembrat, John; George, M Patricia; Knupp, Heather; Ross, Mark; Sharifi-Sanjani, Maryam; Milosevic, Jadranka; St Croix, Claudette; Rajkumar, Revathi; Frid, Maria G; Hunter, Kendall S; Mazzaro, Luciano; Novelli, Enrico M; Stenmark, Kurt R; Gladwin, Mark T; Ahmad, Ferhaan; Champion, Hunter C; Isenberg, Jeffrey S

2013-12-01

Pulmonary hypertension is recognized as a leading cause of morbidity and mortality in patients with sickle cell disease (SCD). We now report benchtop phenotyping from the explanted lungs of the first successful lung transplant in SCD. Pulmonary artery smooth muscle cells (PASMCs) cultured from the explanted lungs were analyzed for proliferate capacity, superoxide (O2 (•-)) production, and changes in key pulmonary arterial hypertension (PAH)-associated molecules and compared with non-PAH PASMCs. Upregulation of several pathologic processes persisted in culture in SCD lung PASMCs in spite of cell passage. SCD lung PASMCs showed growth factor- and serum-independent proliferation, upregulation of matrix genes, and increased O2 (•-) production compared with control cells. Histologic analysis of SCD-associated PAH arteries demonstrated increased and ectopically located extracellular matrix deposition and degradation of elastin fibers. Biomechanical analysis of these vessels confirmed increased arterial stiffening and loss of elasticity. Functional analysis of distal fifth-order pulmonary arteries from these lungs demonstrated increased vasoconstriction to an α1-adrenergic receptor agonist and concurrent loss of both endothelial-dependent and endothelial-independent vasodilation compared with normal pulmonary arteries. This is the first study to evaluate the molecular, cellular, functional, and mechanical changes in end-stage SCD-associated PAH.

Strongly luminescent monolayered MoS2 prepared by effective ultrasound exfoliation.

Science.gov (United States)

Štengl, Václav; Henych, Jiří

2013-04-21

Intense ultrasound in a pressurized batch reactor was used for preparation of monolayered MoS2 nanosheets from natural mineral molybdenite. Exfoliation of bulk MoS2 using ultrasound is an attractive route to large-scale preparation of monolayered crystals. To evaluate the quality of delamination, methods like X-ray diffraction, Raman spectroscopy and microscopic techniques (TEM and AFM) were employed. From single- or few-layered products obtained from intense sonication, MoS2 quantum dots (MoSQDs) were prepared by a one-pot reaction by refluxing exfoliated nanosheets of MoS2 in ethylene glycol under atmospheric pressure. The synthesised MoSQDs were characterised by photoluminescence spectroscopy and laser-scattering particle size analysis. Our easy preparation leads to very strongly green luminescing quantum dots.

Pulmonary Rehabilitation in Improving Lung Function in Patients With Locally Advanced Non-Small Cell Lung Cancer Undergoing Chemoradiation

Science.gov (United States)

2017-04-12

Cachexia; Fatigue; Pulmonary Complications; Radiation Toxicity; Recurrent Non-small Cell Lung Cancer; Stage IIIA Non-small Cell Lung Cancer; Stage IIIB Non-small Cell Lung Cancer; Stage IV Non-small Cell Lung Cancer

Exfoliation of graphene with an industrial dye: teaching an old dog new tricks

Science.gov (United States)

Schlierf, Andrea; Cha, Kitty; Schwab, Matthias Georg; Samorı, Paolo; Palermo, Vincenzo

2014-12-01

We describe the exfoliation, processing and inclusion in polymer composites of few-layers graphene nanoplatelets (GNPs) by using the molecule indanthrone blue sulphonic acid sodium salt (IBS), a very common industrial dyestuff and intermediate for liquid crystal preparation. We show how IBS can be used to successfully exfoliate graphite into few-layers graphene yielding highly stable dispersions in water. To demonstrate that the method is suitable for applications in composites, these graphene-organic hybrids are processed into a commercial commodity polymer (polyvinyl alcohol, PVA), enhancing its electrical bulk conductivity by ten orders of magnitude by adding as few as 3% of GNP. We attribute the good performance of IBS in dispersing GNPs in water to its amphiphilic nature and the tendency to self-assemble through π-π interaction of its large aromatic core with the graphene surface. The molecule studied here, unlike many specialty organic surfactants or solvents commonly known to exfoliate graphene, is already used as a blue pigment dispersant additive in the industrial production of polymers and thus does not need to be removed from the final product.

Exfoliation of graphene with an industrial dye: teaching an old dog new tricks

International Nuclear Information System (INIS)

Schlierf, Andrea; Palermo, Vincenzo; Cha, Kitty; Georg Schwab, Matthias; Samorı, Paolo

2014-01-01

We describe the exfoliation, processing and inclusion in polymer composites of few-layers graphene nanoplatelets (GNPs) by using the molecule indanthrone blue sulphonic acid sodium salt (IBS), a very common industrial dyestuff and intermediate for liquid crystal preparation. We show how IBS can be used to successfully exfoliate graphite into few-layers graphene yielding highly stable dispersions in water. To demonstrate that the method is suitable for applications in composites, these graphene-organic hybrids are processed into a commercial commodity polymer (polyvinyl alcohol, PVA), enhancing its electrical bulk conductivity by ten orders of magnitude by adding as few as 3% of GNP. We attribute the good performance of IBS in dispersing GNPs in water to its amphiphilic nature and the tendency to self-assemble through π–π interaction of its large aromatic core with the graphene surface. The molecule studied here, unlike many specialty organic surfactants or solvents commonly known to exfoliate graphene, is already used as a blue pigment dispersant additive in the industrial production of polymers and thus does not need to be removed from the final product. (paper)

The rapid evolution of CT findings in pulmonary langerhans cell histiocytosis: a case report

International Nuclear Information System (INIS)

Kang, Tae Wook; Lee, Kyung Soo; Cho, Eun Yoon

2007-01-01

Imaging findings of pulmonary Langerhans cell histiocytosis (PLCH) demonstrate evolving changes over time, and the radiological transitions shown by imaging tools may allow a prediction of histopathological activity in PLCH. However, there are no reports describing how rapidly CT findings change with time. We describe a case of PLCH that showed a rapid evolutional change of the pulmonary lesions in a 48-year-old man, in which the nodular lesions showed cystic changes within two-month follow-up periods on chest CT scans

High-quality graphene flakes exfoliated on a flat hydrophobic polymer

DEFF Research Database (Denmark)

Pedrinazzi, Paolo; Caridad, José M.; Mackenzie, David M. A.

2018-01-01

the environment of the graphene flake is completely changed, by encapsulating preselected flakes between hexagonal boron nitride layers. The exfoliation of clean, pristine graphene layers directly on flat polymer substrates enables high performance, supported, and non-encapsulated graphene devices for flexible...

Time-dependent study of the exfoliation process of carbon nanotubes in aqueous dispersions by using UV-visible spectroscopy

NARCIS (Netherlands)

Grossiord, N.; Regev, O.; Loos, J.; Meuldijk, J.; Koning, C.E.

2005-01-01

In this paper we demonstrate that the sonication-driven exfoliation of aggregates and bundles of single-wall carbon nanotubes (SWNTs) in an aqueous surfactant solution can be easily monitored by UV-vis spectroscopy. The different stages of the exfoliation process were directly visualized by

BMP4 Expression Following Stem Cells from Human Exfoliated Deciduous and Carbonate Apatite Transplantation on Rattus norvegicus

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Tania Saskianti

2018-04-01

Full Text Available Background: Alveolar bone defects in children still have a high incidence. Conventional bone graft technique that has been used as a defect therapy is still not effective, so new techniques with tissue engineering approach are needed. Bone Morphogenetic Protein 4 (BMP4 as one of the indicators of osteogenic differentiation has not been widely studied, especially in the transplantation with combination of Stem Cells from Human Exfoliated Deciduous (SHED and carbonate apatite. Aim and Objectives: This research aimed to determine the expression of BMP4 after SHED and carbonate apatite transplantation on Rattus norvegicus. Material and Methods: The combinations of SHED and carbonate apatite were transplanted on alveolar bone defects of 4 rats (Rattus norvegicus as the treatment groups and another 4 rats were transplanted with carbonate apatite as the control groups. After 21 days, staining with Hematoxylin Eosin (HE and Immunohistochemistry (IHC BMP4 was performed. Results: BMP4 expression in the treatment groups was significantly higher when compared to the control groups. Discussion: Carbonate apatite has low crystallization rate and high osteoconductivity that produce more osteoblasts and increased BMP4 expression. Conclusion: The transplantation of SHED and carbonate apatite increased BMP4 expression as an indicator of osteogenic differentiation in rats.

Optimization of the size and yield of graphene oxide sheets in the exfoliation step

OpenAIRE

Botas, Cristina; Pérez, A.M. (Ana); Álvarez, Patricia; Santamaría, Ricardo; Granda, Marcos; Blanco, Clara; Menéndez, Rosa

2017-01-01

In this paper we demonstrate that the yield and size of the graphene oxide sheets (GO) obtained by sonication of graphite oxide (GrO) can be optimized not only by selecting the appropriate exfoliation conditions but also as a function of the crystalline structure of the parent graphite. A larger crystal size in the parent graphite favors GrO exfoliation and yields larger sheets in shorter sonication times, independently of the oxygen content of the GrO. A maximum yield of GO is obtained in al...

New insights in lymphangioleiomyomatosis and pulmonary Langerhans cell histiocytosis

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Olga Torre

2017-09-01

Full Text Available Lymphangioleiomyomatosis (LAM and pulmonary Langerhans cell histiocytosis (PLCH are rare diseases that lead to progressive cystic destruction of the lungs. Despite their distinctive characteristics, these diseases share several features. Patients affected by LAM or PLCH have similar radiological cystic patterns, a similar age of onset, and the possibility of extrapulmonary involvement. In this review, the recent advances in the understanding of the molecular pathogenesis, as well as the current and most promising biomarkers and therapeutic approaches, are described.

Effects of altitude and exercise on pulmonary capillary integrity: evidence for subclinical high-altitude pulmonary edema.

Science.gov (United States)

Eldridge, Marlowe W; Braun, Ruedi K; Yoneda, Ken Y; Walby, William F

2006-03-01

Strenuous exercise may be a significant contributing factor for development of high-altitude pulmonary edema, particularly at low or moderate altitudes. Thus we investigated the effects of heavy cycle ergometer exercise (90% maximal effort) under hypoxic conditions in which the combined effects of a marked increase in pulmonary blood flow and nonuniform hypoxic pulmonary vasoconstriction could add significantly to augment the mechanical stress on the pulmonary microcirculation. We postulated that intense exercise at altitude would result in an augmented permeability edema. We recruited eight endurance athletes and examined their bronchoalveolar lavage fluid (BALF) for red blood cells (RBCs), protein, inflammatory cells, and soluble mediators at 2 and 26 h after intense exercise under normoxic and hypoxic conditions. After heavy exercise, under all conditions, the athletes developed a permeability edema with high BALF RBC and protein concentrations in the absence of inflammation. We found that exercise at altitude (3,810 m) caused significantly greater leakage of RBCs [9.2 (SD 3.1)x10(4) cells/ml] into the alveolar space than that seen with normoxic exercise [5.4 (SD 1.2)x10(4) cells/ml]. At altitude, the 26-h postexercise BALF revealed significantly higher RBC and protein concentrations, suggesting an ongoing capillary leak. Interestingly, the BALF profiles following exercise at altitude are similar to that of early high-altitude pulmonary edema. These findings suggest that pulmonary capillary disruption occurs with intense exercise in healthy humans and that hypoxia augments the mechanical stresses on the pulmonary microcirculation.

Bronchus-associated lymphoid tissue in pulmonary hypertension produces pathologic autoantibodies.

Science.gov (United States)

Colvin, Kelley L; Cripe, Patrick J; Ivy, D Dunbar; Stenmark, Kurt R; Yeager, Michael E

2013-11-01

Autoimmunity has long been associated with pulmonary hypertension. Bronchus-associated lymphoid tissue plays important roles in antigen sampling and self-tolerance during infection and inflammation. We reasoned that activated bronchus-associated lymphoid tissue would be evident in rats with pulmonary hypertension, and that loss of self-tolerance would result in production of pathologic autoantibodies that drive vascular remodeling. We used animal models, histology, and gene expression assays to evaluate the role of bronchus-associated lymphoid tissue in pulmonary hypertension. Bronchus-associated lymphoid tissue was more numerous, larger, and more active in pulmonary hypertension compared with control animals. We found dendritic cells in and around lymphoid tissue, which were composed of CD3(+) T cells over a core of CD45RA(+) B cells. Antirat IgG and plasma from rats with pulmonary hypertension decorated B cells in lymphoid tissue, resistance vessels, and adventitia of large vessels. Lymphoid tissue in diseased rats was vascularized by aquaporin-1(+) high endothelial venules and vascular cell adhesion molecule-positive vessels. Autoantibodies are produced in bronchus-associated lymphoid tissue and, when bound to pulmonary adventitial fibroblasts, change their phenotype to one that may promote inflammation. Passive transfer of autoantibodies into rats caused pulmonary vascular remodeling and pulmonary hypertension. Diminution of lymphoid tissue reversed pulmonary hypertension, whereas immunologic blockade of CCR7 worsened pulmonary hypertension and hastened its onset. Bronchus-associated lymphoid tissue expands in pulmonary hypertension and is autoimmunologically active. Loss of self-tolerance contributes to pulmonary vascular remodeling and pulmonary hypertension. Lymphoid tissue-directed therapies may be beneficial in treating pulmonary hypertension.

Differential concentration-specific effects of caffeine on cell viability, oxidative stress, and cell cycle in pulmonary oxygen toxicity in vitro

International Nuclear Information System (INIS)

Tiwari, Kirti Kumar; Chu, Chun; Couroucli, Xanthi; Moorthy, Bhagavatula; Lingappan, Krithika

2014-01-01

Highlights: • Caffeine at 0.05 mM decreases oxidative stress in hyperoxia. • Caffeine at 1 mM decreases cell viability, increases oxidative stress in hyperoxia. • Caffeine at 1 but not 0.05 mM, abrogates hyperoxia-induced G2/M arrest. - Abstract: Caffeine is used to prevent bronchopulmonary dysplasia (BPD) in premature neonates. Hyperoxia contributes to the development of BPD, inhibits cell proliferation and decreases cell survival. The mechanisms responsible for the protective effect of caffeine in pulmonary oxygen toxicity remain largely unknown. A549 and MLE 12 pulmonary epithelial cells were exposed to hyperoxia or maintained in room air, in the presence of different concentrations (0, 0.05, 0.1 and 1 mM) of caffeine. Caffeine had a differential concentration-specific effect on cell cycle progression, oxidative stress and viability, with 1 mM concentration being deleterious and 0.05 mM being protective. Reactive oxygen species (ROS) generation during hyperoxia was modulated by caffeine in a similar concentration-specific manner. Caffeine at 1 mM, but not at the 0.05 mM concentration decreased the G2 arrest in these cells. Taken together this study shows the novel funding that caffeine has a concentration-specific effect on cell cycle regulation, ROS generation, and cell survival in hyperoxic conditions

Differential concentration-specific effects of caffeine on cell viability, oxidative stress, and cell cycle in pulmonary oxygen toxicity in vitro

Energy Technology Data Exchange (ETDEWEB)

Tiwari, Kirti Kumar; Chu, Chun; Couroucli, Xanthi; Moorthy, Bhagavatula; Lingappan, Krithika, E-mail: lingappa@bcm.edu

2014-08-08

Highlights: • Caffeine at 0.05 mM decreases oxidative stress in hyperoxia. • Caffeine at 1 mM decreases cell viability, increases oxidative stress in hyperoxia. • Caffeine at 1 but not 0.05 mM, abrogates hyperoxia-induced G2/M arrest. - Abstract: Caffeine is used to prevent bronchopulmonary dysplasia (BPD) in premature neonates. Hyperoxia contributes to the development of BPD, inhibits cell proliferation and decreases cell survival. The mechanisms responsible for the protective effect of caffeine in pulmonary oxygen toxicity remain largely unknown. A549 and MLE 12 pulmonary epithelial cells were exposed to hyperoxia or maintained in room air, in the presence of different concentrations (0, 0.05, 0.1 and 1 mM) of caffeine. Caffeine had a differential concentration-specific effect on cell cycle progression, oxidative stress and viability, with 1 mM concentration being deleterious and 0.05 mM being protective. Reactive oxygen species (ROS) generation during hyperoxia was modulated by caffeine in a similar concentration-specific manner. Caffeine at 1 mM, but not at the 0.05 mM concentration decreased the G2 arrest in these cells. Taken together this study shows the novel funding that caffeine has a concentration-specific effect on cell cycle regulation, ROS generation, and cell survival in hyperoxic conditions.

Paracrine effects of bone marrow-derived endothelial progenitor cells: cyclooxygenase-2/prostacyclin pathway in pulmonary arterial hypertension.

Directory of Open Access Journals (Sweden)

Dong-Mei Jiang

Full Text Available BACKGROUND: Endothelial dysfunction is the pathophysiological characteristic of pulmonary arterial hypertension (PAH. Some paracrine factors secreted by bone marrow-derived endothelial progenitor cells (BMEPCs have the potential to strengthen endothelial integrity and function. This study investigated whether BMEPCs have the therapeutic potential to improve monocrotaline (MCT-induced PAH via producing vasoprotective substances in a paracrine fashion. METHODS AND RESULTS: Bone marrow-derived mononuclear cells were cultured for 7 days to yield BMEPCs. 24 hours or 3 weeks after exposure to BMEPCs in vitro or in vivo, the vascular reactivity, cyclooxygenase-2 (COX-2 expression, prostacyclin (PGI2 and cAMP release in isolated pulmonary arteries were examined respectively. Treatment with BMEPCs could improve the relaxation of pulmonary arteries in MCT-induced PAH and BMEPCs were grafted into the pulmonary bed. The COX-2/prostacyclin synthase (PGIS and its progenies PGI2/cAMP were found to be significantly increased in BMEPCs treated pulmonary arteries, and this action was reversed by a selective COX-2 inhibitor, NS398. Moreover, the same effect was also observed in conditioned medium obtained from BMEPCs culture. CONCLUSIONS: Implantation of BMEPCs effectively ameliorates MCT-induced PAH. Factors secreted in a paracrine fashion from BMEPCs promote vasoprotection by increasing the release of PGI2 and level of cAMP.

Orchestration of pulmonary T cell immunity during Mycobacterium tuberculosis infection: immunity interruptus

Science.gov (United States)

Behar, Samuel M.; Carpenter, Stephen M.; Booty, Matthew G.; Barber, Daniel L.; Jayaraman, Pushpa

2014-01-01

Despite the introduction almost a century ago of Mycobacterium bovis BCG (BCG), an attenuated form of M. bovis that is used as a vaccine against Mycobacterium tuberculosis, tuberculosis remains a global health threat and kills more than 1.5 million people each year. This is mostly because BCG fails to prevent pulmonary disease – the contagious form of tuberculosis. Although there have been significant advances in understanding how the immune system responds to infection, the qualities that define protective immunity against M. tuberculosis remain poorly characterized. The ability to predict who will maintain control over the infection and who will succumb to clinical disease would revolutionize our approach to surveillance, control, and treatment. Here we review the current understanding of pulmonary T cell responses following M. tuberculosis infection. While infection elicits a strong immune response that contains infection, M. tuberculosis evades eradication. Traditionally, its intracellular lifestyle and alteration of macrophage function are viewed as the dominant mechanisms of evasion. Now we appreciate that chronic inflammation leads to T cell dysfunction. While this may arise as the host balances the goals of bacterial sterilization and avoidance of tissue damage, it is becoming clear that T cell dysfunction impairs host resistance. Defining the mechanisms that lead to T cell dysfunction is crucial as memory T cell responses are likely to be subject to the same subject to the same pressures. Thus, success of T cell based vaccines is predicated on memory T cells avoiding exhaustion while at the same time not promoting overt tissue damage. PMID:25311810

8,9-Epoxyeicosatrienoic acid analog protects pulmonary artery smooth muscle cells from apoptosis via ROCK pathway

International Nuclear Information System (INIS)

Ma, Jun; Zhang, Lei; Li, Shanshan; Liu, Shulin; Ma, Cui; Li, Weiyang; Falck, J.R.; Manthati, Vijay L.; Reddy, D. Sudarshan; Medhora, Meetha; Jacobs, Elizabeth R.; Zhu, Daling

2010-01-01

Epoxyeicosatrienoic acids (EETs), metabolites of arachidonic acid (AA) catalyzed by cytochrome P450 (CYP), have many essential biologic roles in the cardiovascular system including inhibition of apoptosis in cardiomyocytes. In the present study, we tested the potential of 8,9-EET and derivatives to protect pulmonary artery smooth muscle cells (PASMCs) from starvation induced apoptosis. We found 8,9-epoxy-eicos-11(Z)-enoic acid (8,9-EET analog (214)), but not 8,9-EET, increased cell viability, decreased activation of caspase-3 and caspase-9, and decreased TUNEL-positive cells or nuclear condensation induced by serum deprivation (SD) in PASMCs. These effects were reversed after blocking the Rho-kinase (ROCK) pathway with Y-27632 or HA-1077. Therefore, 8,9-EET analog (214) protects PASMC from serum deprivation-induced apoptosis, mediated at least in part via the ROCK pathway. Serum deprivation of PASMCs resulted in mitochondrial membrane depolarization, decreased expression of Bcl-2 and enhanced expression of Bax, all effects were reversed by 8,9-EET analog (214) in a ROCK dependent manner. Because 8,9-EET and not the 8,9-EET analog (214) protects pulmonary artery endothelial cells (PAECs), these observations suggest the potential to differentially promote apoptosis or survival with 8,9-EET or analogs in pulmonary arteries.

8,9-Epoxyeicosatrienoic acid analog protects pulmonary artery smooth muscle cells from apoptosis via ROCK pathway

Energy Technology Data Exchange (ETDEWEB)

Ma, Jun; Zhang, Lei; Li, Shanshan [Department of Biopharmaceutical Sciences, College of Pharmacy, Harbin Medical University, 157 Baojian Road, Nangang District, Harbin, Heilongjiang 150081 (China); Liu, Shulin [Department of Biopharmaceutical Sciences, College of Pharmacy, Harbin Medical University, 157 Baojian Road, Nangang District, Harbin, Heilongjiang 150081 (China); Bio-pharmaceutical Key Laboratory of Heilongjiang Province, Harbin 150081 (China); Ma, Cui [Department of Biopharmaceutical Sciences, College of Pharmacy, Harbin Medical University, 157 Baojian Road, Nangang District, Harbin, Heilongjiang 150081 (China); Li, Weiyang [Mudanjiang Medical College, Mudanjiang 157011 (China); Falck, J.R.; Manthati, Vijay L.; Reddy, D. Sudarshan [University of Texas Southwestern Medical Center, Dallas, TX 75390 (United States); Medhora, Meetha; Jacobs, Elizabeth R. [Division of Pulmonary and Critical Care, Department of Medicine, Cardiovascular Center, Medical College of Wisconsin, Milwaukee, WI 53226 (United States); Zhu, Daling, E-mail: dalingz@yahoo.com [Department of Biopharmaceutical Sciences, College of Pharmacy, Harbin Medical University, 157 Baojian Road, Nangang District, Harbin, Heilongjiang 150081 (China); Bio-pharmaceutical Key Laboratory of Heilongjiang Province, Harbin 150081 (China)

2010-08-15

Epoxyeicosatrienoic acids (EETs), metabolites of arachidonic acid (AA) catalyzed by cytochrome P450 (CYP), have many essential biologic roles in the cardiovascular system including inhibition of apoptosis in cardiomyocytes. In the present study, we tested the potential of 8,9-EET and derivatives to protect pulmonary artery smooth muscle cells (PASMCs) from starvation induced apoptosis. We found 8,9-epoxy-eicos-11(Z)-enoic acid (8,9-EET analog (214)), but not 8,9-EET, increased cell viability, decreased activation of caspase-3 and caspase-9, and decreased TUNEL-positive cells or nuclear condensation induced by serum deprivation (SD) in PASMCs. These effects were reversed after blocking the Rho-kinase (ROCK) pathway with Y-27632 or HA-1077. Therefore, 8,9-EET analog (214) protects PASMC from serum deprivation-induced apoptosis, mediated at least in part via the ROCK pathway. Serum deprivation of PASMCs resulted in mitochondrial membrane depolarization, decreased expression of Bcl-2 and enhanced expression of Bax, all effects were reversed by 8,9-EET analog (214) in a ROCK dependent manner. Because 8,9-EET and not the 8,9-EET analog (214) protects pulmonary artery endothelial cells (PAECs), these observations suggest the potential to differentially promote apoptosis or survival with 8,9-EET or analogs in pulmonary arteries.

Mycophenolate mofetil attenuates pulmonary arterial hypertension in rats

International Nuclear Information System (INIS)

Suzuki, Chihiro; Takahashi, Masafumi; Morimoto, Hajime; Izawa, Atsushi; Ise, Hirohiko; Hongo, Minoru; Hoshikawa, Yasushi; Ito, Takayuki; Miyashita, Hiroshi; Kobayashi, Eiji; Shimada, Kazuyuki; Ikeda, Uichi

2006-01-01

Pulmonary arterial hypertension (PAH) is characterized by abnormal proliferation of smooth muscle cells (SMCs), leading to occlusion of pulmonary arterioles, right ventricular (RV) hypertrophy, and death. We investigated whether mycophenolate mofetil (MMF), a potent immunosuppresssant, prevents the development of monocrotaline (MCT)-induced PAH in rats. MMF effectively decreased RV systolic pressure and RV hypertrophy, and reduced the medial thickness of pulmonary arteries. MMF significantly inhibited the number of proliferating cell nuclear antigen (PCNA)-positive cells, infiltration of macrophages, and expression of P-selectin and interleukin-6 on the endothelium of pulmonary arteries. The infiltration of T cells and mast cells was not affected by MMF. In vitro experiments revealed that mycophenolic acid (MPA), an active metabolite of MMF, dose-dependently inhibited proliferation of human pulmonary arterial SMCs. MMF attenuated the development of PAH through its anti-inflammatory and anti-proliferative properties. These findings provide new insight into the potential role of immunosuppressants in the treatment of PAH

Electrolytic exfoliation of graphite in water with multifunctional electrolytes: en route towards high quality, oxide-free graphene flakes.

Science.gov (United States)

Munuera, J M; Paredes, J I; Villar-Rodil, S; Ayán-Varela, M; Martínez-Alonso, A; Tascón, J M D

2016-02-07

Electrolytic--usually referred to as electrochemical--exfoliation of graphite in water under anodic potential holds enormous promise as a simple, green and high-yield method for the mass production of graphene, but currently suffers from several drawbacks that hinder its widespread adoption, one of the most critical being the oxidation and subsequent structural degradation of the carbon lattice that is usually associated with such a production process. To overcome this and other limitations, we introduce and implement the concept of multifunctional electrolytes. The latter are amphiphilic anions (mostly polyaromatic hydrocarbons appended with sulfonate groups) that play different relevant roles as (1) an intercalating electrolyte to trigger exfoliation of graphite into graphene flakes, (2) a dispersant to afford stable aqueous colloidal suspensions of the flakes suitable for further use, (3) a sacrificial agent to prevent graphene oxidation during exfoliation and (4) a linker to promote nanoparticle anchoring on the graphene flakes, yielding functional hybrids. The implementation of this strategy with some selected amphiphiles even furnishes anodically exfoliated graphenes of a quality similar to that of flakes produced by direct, ultrasound- or shear-induced exfoliation of graphite in the liquid phase (i.e., almost oxide- and defect-free). These high quality materials were used for the preparation of catalytically efficient graphene-Pt nanoparticle hybrids, as demonstrated by model reactions (reduction of nitroarenes). The multifunctional performance of these electrolytes is also discussed and rationalized, and a mechanistic picture of their oxidation-preventing ability is proposed. Overall, the present results open the prospect of anodic exfoliation as a competitive method for the production of very high quality graphene flakes.

B cell activating factor is central to bleomycin- and IL-17-mediated experimental pulmonary fibrosis.

Science.gov (United States)

François, Antoine; Gombault, Aurélie; Villeret, Bérengère; Alsaleh, Ghada; Fanny, Manoussa; Gasse, Paméla; Adam, Sylvain Marchand; Crestani, Bruno; Sibilia, Jean; Schneider, Pascal; Bahram, Seiamak; Quesniaux, Valérie; Ryffel, Bernhard; Wachsmann, Dominique; Gottenberg, Jacques-Eric; Couillin, Isabelle

2015-01-01

Idiopathic pulmonary fibrosis (IPF) is a progressive devastating, yet untreatable fibrotic disease of unknown origin. We investigated the contribution of the B-cell activating factor (BAFF), a TNF family member recently implicated in the regulation of pathogenic IL-17-producing cells in autoimmune diseases. The contribution of BAFF was assessed in a murine model of lung fibrosis induced by airway administered bleomycin. We show that murine BAFF levels were strongly increased in the bronchoalveolar space and lungs after bleomycin exposure. We identified Gr1(+) neutrophils as an important source of BAFF upon BLM-induced lung inflammation and fibrosis. Genetic ablation of BAFF or BAFF neutralization by a soluble receptor significantly attenuated pulmonary fibrosis and IL-1β levels. We further demonstrate that bleomycin-induced BAFF expression and lung fibrosis were IL-1β and IL-17A dependent. BAFF was required for rIL-17A-induced lung fibrosis and augmented IL-17A production by CD3(+) T cells from murine fibrotic lungs ex vivo. Finally we report elevated levels of BAFF in bronchoalveolar lavages from IPF patients. Our data therefore support a role for BAFF in the establishment of pulmonary fibrosis and a crosstalk between IL-1β, BAFF and IL-17A. Copyright © 2014 Elsevier Ltd. All rights reserved.

Rockfall triggering by cyclic thermal stressing of exfoliation fractures

Science.gov (United States)

Collins, Brian D.; Stock, Greg M.

2016-01-01

Exfoliation of rock deteriorates cliffs through the formation and subsequent opening of fractures, which in turn can lead to potentially hazardous rockfalls. Although a number of mechanisms are known to trigger rockfalls, many rockfalls occur during periods when likely triggers such as precipitation, seismic activity and freezing conditions are absent. It has been suggested that these enigmatic rockfalls may occur due to solar heating of rock surfaces, which can cause outward expansion. Here we use data from 3.5 years of field monitoring of an exfoliating granite cliff in Yosemite National Park in California, USA, to assess the magnitude and temporal pattern of thermally induced rock deformation. From a thermodynamic analysis, we find that daily, seasonal and annual temperature variations are sufficient to drive cyclic and cumulative opening of fractures. Application of fracture theory suggests that these changes can lead to further fracture propagation and the consequent detachment of rock. Our data indicate that the warmest times of the day and year are particularly conducive to triggering rockfalls, and that cyclic thermal forcing may enhance the efficacy of other, more typical rockfall triggers.

Exfoliation of Threading Dislocation-Free, Single-Crystalline, Ultrathin Gallium Nitride Nanomembranes

KAUST Repository

Elafandy, Rami T.; Cha, Dong Kyu; Majid, Mohammed Abdul; Ng, Tien Khee; Ooi, Boon S.; Zhao, Lan

2014-01-01

-efficiency, low-cost, GaN-based heterostructure devices. For the first time, the chemical exfoliation of completely TD-free, single-crystalline, ultrathin (tens of nanometers) GaN nanomembranes is demonstrated using UV-assisted electroless chemical etching

Mitigation of Late Renal and Pulmonary Injury After Hematopoietic Stem Cell Transplantation

Energy Technology Data Exchange (ETDEWEB)

Cohen, Eric P., E-mail: Eric.Cohen2@va.gov [Department of Medicine, Medical College of Wisconsin, Milwaukee, Wisconsin (United States); Bedi, Manpreet; Irving, Amy A. [Department of Radiation Oncology, Medical College of Wisconsin, Milwaukee, Wisconsin (United States); Jacobs, Elizabeth; Tomic, Rade [Department of Medicine, Medical College of Wisconsin, Milwaukee, Wisconsin (United States); Klein, John [Department of Biostatistics, Medical College of Wisconsin, Milwaukee, Wisconsin (United States); Lawton, Colleen A.; Moulder, John E. [Department of Radiation Oncology, Medical College of Wisconsin, Milwaukee, Wisconsin (United States)

2012-05-01

Purpose: To update the results of a clinical trial that assessed whether the angiotensin-converting enzyme inhibitor captopril was effective in mitigating chronic renal failure and pulmonary-related mortality in subjects undergoing total body irradiation (TBI) in preparation for hematopoietic stem cell transplantation (HSCT). Methods and Materials: Updated records of the 55 subjects who were enrolled in this randomized controlled trial were analyzed. Twenty-eight patients received captopril, and 27 patients received placebo. Definitions of TBI-HSCT-related chronic renal failure (and relapse) were the same as those in the 2007 analysis. Pulmonary-related mortality was based on clinical or autopsy findings of pulmonary failure or infection as the primary cause of death. Follow-up data for overall and pulmonary-related mortality were supplemented by use of the National Death Index. Results: The risk of TBI-HSCT-related chronic renal failure was lower in the captopril group (11% at 4 years) than in the placebo group (17% at 4 years), but this was not statistically significant (p > 0.2). Analysis of mortality was greatly extended by use of the National Death Index, and no patients were lost to follow-up for reasons other than death prior to 67 months. Patient survival was higher in the captopril group than in the placebo group, but this was not statistically significant (p > 0.2). The improvement in survival was influenced more by a decrease in pulmonary mortality (11% risk at 4 years in the captopril group vs. 26% in the placebo group, p = 0.15) than by a decrease in chronic renal failure. There was no adverse effect on relapse risk (p = 0.4). Conclusions: Captopril therapy produces no detectable adverse effects when given after TBI. Captopril therapy reduces overall and pulmonary-related mortality after radiation-based HSCT, and there is a trend toward mitigation of chronic renal failure.

Mitigation of Late Renal and Pulmonary Injury After Hematopoietic Stem Cell Transplantation

International Nuclear Information System (INIS)

Cohen, Eric P.; Bedi, Manpreet; Irving, Amy A.; Jacobs, Elizabeth; Tomic, Rade; Klein, John; Lawton, Colleen A.; Moulder, John E.

2012-01-01

Purpose: To update the results of a clinical trial that assessed whether the angiotensin-converting enzyme inhibitor captopril was effective in mitigating chronic renal failure and pulmonary-related mortality in subjects undergoing total body irradiation (TBI) in preparation for hematopoietic stem cell transplantation (HSCT). Methods and Materials: Updated records of the 55 subjects who were enrolled in this randomized controlled trial were analyzed. Twenty-eight patients received captopril, and 27 patients received placebo. Definitions of TBI-HSCT-related chronic renal failure (and relapse) were the same as those in the 2007 analysis. Pulmonary-related mortality was based on clinical or autopsy findings of pulmonary failure or infection as the primary cause of death. Follow-up data for overall and pulmonary-related mortality were supplemented by use of the National Death Index. Results: The risk of TBI-HSCT-related chronic renal failure was lower in the captopril group (11% at 4 years) than in the placebo group (17% at 4 years), but this was not statistically significant (p > 0.2). Analysis of mortality was greatly extended by use of the National Death Index, and no patients were lost to follow-up for reasons other than death prior to 67 months. Patient survival was higher in the captopril group than in the placebo group, but this was not statistically significant (p > 0.2). The improvement in survival was influenced more by a decrease in pulmonary mortality (11% risk at 4 years in the captopril group vs. 26% in the placebo group, p = 0.15) than by a decrease in chronic renal failure. There was no adverse effect on relapse risk (p = 0.4). Conclusions: Captopril therapy produces no detectable adverse effects when given after TBI. Captopril therapy reduces overall and pulmonary-related mortality after radiation-based HSCT, and there is a trend toward mitigation of chronic renal failure.

Management of germ cell testicular cancer with pulmonary metastases

International Nuclear Information System (INIS)

Schnorrer, M.; Carsky, S.; Ondrus, D.; Hornak, M.; Belan, V.; Kausitz, J.; Matoska, J.

1996-01-01

Twenty eight patients with germ cell testicular pulmonary metastases received primary chemotherapy including bleomycin, etoposide, and cisplatin. Complete response (CR) was achieved in 21 (75%) patients, in 11 of them CR was achieved following chemotherapy alone. Post-chemotherapy surgery of residual mass performed in 12 (42.9%) patients with normalized serum tumor markers. Retroperitoneal lymph node dissection was performed in one patient, pulmonary surgery in four, and both post-chemotherapy treatments in 7 patients. Overall cure rate was 89.3%, 26 (92.9%) patients are still alive at a mean follow-up of 19.7+ months (range, 3-34+ months) after the treatment start. Two (7.1%) died: one of them due to disease progression during chemotherapy, and the second one due to postoperative complication (acute respiratory failure). Relapse of disease was observed in one patient 21 months following CR achievement, and sequential chemotherapy was introduced. Authors recommend surgical remove of all radiologically detected residual deposits, because the available imaging methods are not adequate for determining the histologic composition of residual mass, which is decisive for further therapy and has prognostic value. (author)

Theophylline prevents NAD+ depletion via PARP-1 inhibition in human pulmonary epithelial cells

International Nuclear Information System (INIS)

Moonen, Harald J.J.; Geraets, Liesbeth; Vaarhorst, Anika; Bast, Aalt; Wouters, Emiel F.M.; Hageman, Geja J.

2005-01-01

Oxidative DNA damage, as occurs during exacerbations in chronic obstructive pulmonary disease (COPD), highly activates the nuclear enzyme poly(ADP-ribose)polymerase-1 (PARP-1). This can lead to cellular depletion of its substrate NAD + , resulting in an energy crisis and ultimately in cell death. Inhibition of PARP-1 results in preservation of the intracellular NAD + pool, and of NAD + -dependent cellular processes. In this study, PARP-1 activation by hydrogen peroxide decreased intracellular NAD + levels in human pulmonary epithelial cells, which was found to be prevented in a dose-dependent manner by theophylline, a widely used compound in the treatment of COPD. This enzyme inhibition by theophylline was confirmed in an ELISA using purified human PARP-1 and was found to be competitive by nature. These findings provide new mechanistic insights into the therapeutic effect of theophylline in oxidative stress-induced lung pathologies

Comparison on exfoliated graphene nano-sheets and triturated graphite nano-particles for mode-locking the Erbium-doped fibre lasers

Science.gov (United States)

Yang, Chun-Yu; Lin, Yung-Hsiang; Wu, Chung-Lun; Cheng, Chih-Hsien; Tsai, Din-Ping; Lin, Gong-Ru

2018-06-01

Comparisons on exfoliated graphene nano-sheets and triturated graphite nano-particles for mode-locking the Erbium-doped fiber lasers (EDFLs) are performed. As opposed to the graphite nano-particles obtained by physically triturating the graphite foil, the tri-layer graphene nano-sheets is obtained by electrochemically exfoliating the graphite foil. To precisely control the size dispersion and the layer number of the exfoliated graphene nano-sheet, both the bias of electrochemical exfoliation and the speed of centrifugation are optimized. Under a threshold exfoliation bias of 3 volts and a centrifugation at 1000 rpm, graphene nano-sheets with an average diameter of 100  ±  40 nm can be obtained. The graphene nano-sheets with an area density of 15 #/µm2 are directly imprinted onto the end-face of a single-mode fiber made patchcord connector inside the EDFL cavity. Such electrochemically exfoliated graphene nano-sheets show comparable saturable absorption with standard single-graphene and perform the self-amplitude modulation better than physically triturated graphite nano-particles. The linear transmittance and modulation depth of the inserted graphene nano-sheets are 92.5% and 53%, respectively. Under the operation with a power gain of 21.5 dB, the EDFL can be passively mode-locked to deliver a pulsewidth of 454.5 fs with a spectral linewidth of 5.6 nm. The time-bandwidth product of 0.31 is close to the transform limit. The Kelly sideband frequency spacing of 1.34 THz is used to calculate the chirp coefficient as  ‑0.0015.

C4.4A as a biomarker in pulmonary adenocarcinoma and squamous cell carcinoma

DEFF Research Database (Denmark)

Jacobsen, Benedikte; Kriegbaum, Mette Camilla; Santoni-Rugiu, Eric

2014-01-01

to invasive carcinomas of the lung, i.e., in bronchial hyperplasia/metaplasia and atypical adenomatous hyperplasia. In the stages leading to pulmonary squamous cell carcinoma, expression is sustained in dysplasia, carcinoma in situ and invasive carcinomas, and this pertains to the normal presence of C4.4A...... in squamous epithelium. In pulmonary adenocarcinomas, a fraction of cases is positive for C4.4A, which is surprising, given the origin of these carcinomas from mucin-producing and not squamous epithelium. Interestingly, this correlates with a highly compromised patient survival and a predominant solid tumor...

Preparation and Characterization of EG-Chitosan Nanocomposites via Direct Exfoliation: A Green Methodology

Directory of Open Access Journals (Sweden)

Christian Demitri

2015-12-01

Full Text Available In this study, free-standing expanded graphite chitosan (EG-chitosan nanocomposite films have been prepared using a novel green and simple preparation method, starting from a commercial expandable graphite (GIC. The in situ exfoliation of GIC by a solvent-free sonication method was monitored as a function of the process parameters using X-ray diffraction (XRD, transmission electron microscopy (TEM, dynamic light scattering (DLS and UV-visible transmittance (UV-VIS analyses. The optimal process parameters were selected in order to obtain an efficient dispersion of EG in chitosan solutions. The effective EG amount after the in situ exfoliation was also determined by thermogravimetric analyses.

Hole-doping of mechanically exfoliated graphene by confined hydration layers

NARCIS (Netherlands)

Bollmann, Tjeerd Rogier Johannes; Antipina, L.Y.; Temmen, M.; Reichling, M.; Sorokin, P.B.

2015-01-01

By the use of non-contact atomic force microscopy (NC-AFM) and Kelvin probe force microscopy (KPFM), we measure the local surface potential of mechanically exfoliated graphene on the prototypical insulating hydrophilic substrate of CaF2(111). Hydration layers confined between the graphene and the

Black tea assisted exfoliation using a kitchen mixer allowing one-step production of graphene

Science.gov (United States)

Ismail, Zulhelmi; Farhana Abu Kassim, Nurul; Hannifa Abdullah, Abu; Sakinah Zainal Abidin, Anis; Sameha Ismail, Fadwa; Yusoh, Kamal

2017-07-01

A kitchen mixer is one of the possible tools for the exfoliation of graphene. While organic solvents such as NMP or DMF are suitable for the exfoliation of graphite, the majority are toxic and dangerously harmful when exposed to humans and the environment. Therefore, an alternative solvent must be proposed for green and sustainable production of graphene. In this initial work, we have developed a new synthesis method for graphene through the direct exfoliation of graphite in commercial black tea. We found that our maximum yield concentration of graphene is Y  =  0.032 mg ml-l after 15 min of mixing. From the data of Raman, the level of defects in our produced graphene is suggested as being very minor (I D/I G  =  0.17), despite possible graphene functionalization by oxygen groups in tea. Incorporation of our graphene into PMMA results in shifting the onset temperature from 300 °C to 326 °C, which impressively validates the potential of the produced graphene as a thermal reinforcement material for polymer composites.

Cytotoxicity of accelerated white MTA and Malaysian white Portland cement on stem cells from human exfoliated deciduous teeth (SHED): An in vitro study.

Science.gov (United States)

Ong, Ren Ming; Luddin, Norhayati; Ahmed, Hany Mohamed Aly; Omar, Nor Shamsuria

2012-12-01

The aim of this study was to compare the cytotoxicity of accelerated-set white MTA (AWMTA) and accelerated-set Malaysian white PC (AMWPC) on stem cells from human exfoliated deciduous teeth (SHED). The test materials were introduced into paraffin wax moulds after mixing with calcium chloride dihydrate and sterile distilled water. Subsequently, the set cement specimens were sterilized, incubated in a prepared Dulbecco's modified Eagle medium (DMEM) for seven days. The biomarker CD166 was used for characterization of SHED using flow cytometry. The material extracts were diluted at five different concentrations and incubated for 72h with SHED. The cell viability was evaluated using Dimethylthiazol diphenyltetrazolium bromide (MTT) assay, and the data was analysed using Mann-Whitney test (P<0.05). The results showed that AWMTA revealed significantly greater cell viability at 25 and 12.5mg/ml concentrations (P<0.05). Concomitantly, AMWPC exhibited greater cell viability at concentrations <12.5mg/ml and the results were significant at 1.563mg/ml (P<0.05). Both materials demonstrated moderate cytotoxicity at 25mg/ml and slight cytotoxicity at 6.25 and 3.125mg/ml. At 1.563mg/ml, no cytotoxic activity was merely observed with AMWPC. In conclusion, AMWPC exhibited favourable and comparable cell viability to that of AWMTA, and has the potential to be used as an alternative and less costly material in dental applications. Copyright © 2012. Published by Elsevier B.V.

Packaging material and flexible medical tubing containing thermally exfoliated graphite oxide

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Prud'homme, Robert K. (Inventor); Aksay, Ilhan A. (Inventor)

2011-01-01

A packaging material or flexible medical tubing containing a modified graphite oxide material, which is a thermally exfoliated graphite oxide with a surface area of from about 300 m.sup.2/g to 2600 m.sup.2/g.

Understanding delayed T-cell priming, lung recruitment, and airway luminal T-cell responses in host defense against pulmonary tuberculosis.

Science.gov (United States)

Shaler, Christopher R; Horvath, Carly; Lai, Rocky; Xing, Zhou

2012-01-01

Mycobacterium tuberculosis (M.tb), the causative bacterium of pulmonary tuberculosis (TB), is a serious global health concern. Central to M.tb effective immune avoidance is its ability to modulate the early innate inflammatory response and prevent the establishment of adaptive T-cell immunity for nearly three weeks. When compared with other intracellular bacterial lung pathogens, such as Legionella pneumophila, or even closely related mycobacterial species such as M. smegmatis, this delay is astonishing. Customarily, the alveolar macrophage (AM) acts as a sentinel, detecting and alerting surrounding cells to the presence of an invader. However, in the case of M.tb, this may be impaired, thus delaying the recruitment of antigen-presenting cells (APCs) to the lung. Upon uptake by APC populations, M.tb is able to subvert and delay the processing of antigen, MHC class II loading, and the priming of effector T cell populations. This delay ultimately results in the deferred recruitment of effector T cells to not only the lung interstitium but also the airway lumen. Therefore, it is of upmost importance to dissect the mechanisms that contribute to the delayed onset of immune responses following M.tb infection. Such knowledge will help design the most effective vaccination strategies against pulmonary TB.

High-efficiency exfoliation of layered materials into 2D nanosheets in switchable CO2/Surfactant/H2O system

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Wang, Nan; Xu, Qun; Xu, Shanshan; Qi, Yuhang; Chen, Meng; Li, Hongxiang; Han, Buxing

2015-11-01

Layered materials present attractive and important properties due to their two-dimensional (2D) structure, allowing potential applications including electronics, optoelectronics, and catalysis. However, fully exploiting the outstanding properties will require a method for their efficient exfoliation. Here we present that a series of layered materials can be successfully exfoliated into single- and few-layer nanosheets using the driving forces coming from the phase inversion, i.e., from micelles to reverse micelles in the emulsion microenvironment built by supercritical carbon dioxide (SC CO2). The effect of variable experimental parameters including CO2 pressure, ethanol/water ratio, and initial concentration of bulk materials on the exfoliation yield have been investigated. Moreover, we demonstrate that the exfoliated 2D nanosheets have their worthwhile applications, for example, graphene can be used to prepare conductive paper, MoS2 can be used as fluorescent label to perform cellular labelling, and BN can effectively reinforce polymers leading to the promising mechanical properties.

Production of High-quality Few-layer Graphene Flakes by Intercalation and Exfoliation

KAUST Repository

Alzahrani, Areej A.

2017-01-01

, the source material was a commercially available graphiteintercalated compound, also known as expandable graphite. Several exfoliation-inducing tools were investigated including the use of blenders, homogenizers, and ultrasonic processors. To aid

Mycobacterium tuberculosis strains exhibit differential and strain-specific molecular signatures in pulmonary epithelial cells.

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Mvubu, Nontobeko Eunice; Pillay, Balakrishna; Gamieldien, Junaid; Bishai, William; Pillay, Manormoney

2016-12-01

Although pulmonary epithelial cells are integral to innate and adaptive immune responses during Mycobacterium tuberculosis infection, global transcriptomic changes in these cells remain largely unknown. Changes in gene expression induced in pulmonary epithelial cells infected with M. tuberculosis F15/LAM4/KZN, F11, F28, Beijing and Unique genotypes were investigated by RNA sequencing (RNA-Seq). The Illumina HiSeq 2000 platform generated 50 bp reads that were mapped to the human genome (Hg19) using Tophat (2.0.10). Differential gene expression induced by the different strains in infected relative to the uninfected cells was quantified and compared using Cufflinks (2.1.0) and MeV (4.0.9), respectively. Gene expression varied among the strains with the total number of genes as follows: F15/LAM4/KZN (1187), Beijing (1252), F11 (1639), F28 (870), Unique (886) and H37Rv (1179). A subset of 292 genes was commonly induced by all strains, where 52 genes were down-regulated while 240 genes were up-regulated. Differentially expressed genes were compared among the strains and the number of induced strain-specific gene signatures were as follows: F15/LAM4/KZN (138), Beijing (52), F11 (255), F28 (55), Unique (186) and H37Rv (125). Strain-specific molecular gene signatures associated with functional pathways were observed only for the Unique and H37Rv strains while certain biological functions may be associated with other strain signatures. This study demonstrated that strains of M. tuberculosis induce differential gene expression and strain-specific molecular signatures in pulmonary epithelial cells. Specific signatures induced by clinical strains of M. tuberculosis can be further explored for novel host-associated biomarkers and adjunctive immunotherapies. Copyright © 2016 Elsevier Ltd. All rights reserved.

Quercetin Inhibits Pulmonary Arterial Endothelial Cell Transdifferentiation Possibly by Akt and Erk1/2 Pathways

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Shian Huang

2017-01-01

Full Text Available This study aimed to investigate the effects and mechanisms of quercetin on pulmonary arterial endothelial cell (PAEC transdifferentiation into smooth muscle-like cells. TGF-β1-induced PAEC transdifferentiation models were applied to evaluate the pharmacological actions of quercetin. PAEC proliferation was detected with CCK8 method and BurdU immunocytochemistry. Meanwhile, the identification and transdifferentiation of PAECs were determined by FVIII immunofluorescence staining and α-SMA protein expression. The related mechanism was elucidated based on the levels of Akt and Erk1/2 signal pathways. As a result, quercetin effectively inhibited the TGF-β1-induced proliferation and transdifferentiation of the PAECs and activation of Akt/Erk1/2 cascade in the cells. In conclusion, quercetin is demonstrated to be effective for pulmonary arterial hypertension (PAH probably by inhibiting endothelial transdifferentiation possibly via modulating Akt and Erk1/2 expressions.

CXCR4-mediated osteosarcoma growth and pulmonary metastasis is promoted by mesenchymal stem cells through VEGF.

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Zhang, Peng; Dong, Ling; Yan, Kang; Long, Hua; Yang, Tong-Tao; Dong, Ming-Qing; Zhou, Yong; Fan, Qing-Yu; Ma, Bao-An

2013-10-01

Chemokines and chemokine receptor 4 (CXCR4) play an important role in metastasis. CXCR4 is also expressed in the human osteosarcoma cell line 9607-F5M2 (F5M2), which has a high tumorigenic ability and potential for spontaneous pulmonary metastasis. Mesenchymal stem cells (MSCs) contribute to the formation of the tumor stroma and promote metastasis. However, mechanisms underlying the promotion of osteosarcoma growth and pulmonary metastasis by MSCs are still elusive. Our study co-injected the human MSCs and F5M2 cells into the caudal vein of nude mice. The total number of tumor nodules per lung was significantly increased in the F5M2+MSC group compared to the other groups (control, F5M2 cells alone and MSCs alone) at week six. Moreover, a high number of Dil-labeled MSCs was present also at the osteosarcoma metastasis sites in the lung. Using Transwell assays, we found that F5M2 cells migrate towards MSCs, while the CXCR4 inhibitor AMD3100 decreased the migration potential of F5M2 cells towards MSCs. Furthermore, upon treatment with F5M2-conditioned medium, MSCs expressed and secreted higher levels of VEGF as determined by immunohistochemistry, western blotting and ELISA, respectively. Importantly, co-cultured with F5M2 cells, MSCs expressed and secreted higher VEGF levels, while AMD3100 dramatically decreased the VEGF secretion by MSCs. However, CXCR4 expression on F5M2 cells was not significantly increased in the co-culture system. Additionally, VEGF increased the proliferation of both MSCs and F5M2 cells. These findings suggest that CXCR4-mediated osteosarcoma growth and pulmonary metastasis are promoted by MSCs through VEGF.

Pleiotropic effects of statins in distal human pulmonary artery smooth muscle cells

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Butrous Ghazwan S

2011-10-01

Full Text Available Abstract Background Recent clinical data suggest statins have transient but significant effects in patients with pulmonary arterial hypertension. In this study we explored the molecular effects of statins on distal human pulmonary artery smooth muscle cells (PASMCs and their relevance to proliferation and apoptosis in pulmonary arterial hypertension. Methods Primary distal human PASMCs from patients and controls were treated with lipophilic (simvastatin, atorvastatin, mevastatin and fluvastatin, lipophobic (pravastatin and nitric-oxide releasing statins and studied in terms of their DNA synthesis, proliferation, apoptosis, matrix metalloproteinase-9 and endothelin-1 release. Results Treatment of human PASMCs with selected statins inhibited DNA synthesis, proliferation and matrix metalloproteinase-9 production in a concentration-dependent manner. Statins differed in their effectiveness, the rank order of anti-mitogenic potency being simvastatin > atorvastatin > > pravastatin. Nevertheless, a novel nitric oxide-releasing derivative of pravastatin (NCX 6550 was effective. Lipophilic statins, such as simvastatin, also enhanced the anti-proliferative effects of iloprost and sildenafil, promoted apoptosis and inhibited the release of the mitogen and survival factor endothelin-1. These effects were reversed by mevalonate and the isoprenoid intermediate geranylgeranylpyrophosphate and were mimicked by inhibitors of the Rho and Rho-kinase. Conclusions Lipophilic statins exert direct effects on distal human PASMCs and are likely to involve inhibition of Rho GTPase signalling. These findings compliment some of the recently documented effects in patients with pulmonary arterial hypertension.

Influence of Retrogression and Re-aging on the Exfoliation Corrosion Behavior of AA 7085 Sheets

Energy Technology Data Exchange (ETDEWEB)

Krishnan, Ajay; Raja, V. S. [Indian Institute of Technology Bombay, Mumbai (India); Mukhopadhyay, A. K. [Defence Metallurgical Research Laboratory, Hyderabad (India)

2016-08-15

An attempt has been made to understand the influence of retrogression and re-aging (RRA) on the exfoliation corrosion behaviour of AA 7085 alloy in comparison with the peak aged condition (PA). Immersion tests using ASTM G34 and studies involving electrochemical impedance spectroscopy showed that the RRA treated alloy provided higher resistance to exfoliation corrosion than the PA treated alloy. The improved resistance was attributed to the enhanced Cu content and the discontinuous nature of the grain boundary precipitate, which was revealed through transmission electron microscopy.

A flexible and transparent graphene/ZnO nanorod hybrid structure fabricated by exfoliating a graphite substrate

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Nam, Gwang-Hee; Baek, Seong-Ho; Cho, Chang-Hee; Park, Il-Kyu

2014-09-01

We demonstrate the fabrication of a graphene/ZnO nanorod (NR) hybrid structure by mechanical exfoliation of ZnO NRs grown on a graphite substrate. We confirmed the existence of graphene sheets on the hybrid structure by analyzing the Raman spectra and current-voltage (I-V) characteristics. The Raman spectra of the exfoliated graphene/ZnO NR hybrid structure show G and 2D band peaks that are shifted to lower wavenumbers, indicating that the exfoliated graphene layer exists under a significant amount of strain. The I-V characteristics of the graphene/ZnO NR hybrid structure show current flow through the graphene layer, while no current flow is observed on the ZnO NR/polydimethylsiloxane (PDMS) composite without graphene, thereby indicating that the few-layer graphene was successfully transferred onto the hybrid structure. A piezoelectric nanogenerator is demonstrated by using the fabricated graphene/ZnO NR hybrid structure. The nanogenerator exhibits stable output voltage up to 3.04 V with alternating current output characteristics.We demonstrate the fabrication of a graphene/ZnO nanorod (NR) hybrid structure by mechanical exfoliation of ZnO NRs grown on a graphite substrate. We confirmed the existence of graphene sheets on the hybrid structure by analyzing the Raman spectra and current-voltage (I-V) characteristics. The Raman spectra of the exfoliated graphene/ZnO NR hybrid structure show G and 2D band peaks that are shifted to lower wavenumbers, indicating that the exfoliated graphene layer exists under a significant amount of strain. The I-V characteristics of the graphene/ZnO NR hybrid structure show current flow through the graphene layer, while no current flow is observed on the ZnO NR/polydimethylsiloxane (PDMS) composite without graphene, thereby indicating that the few-layer graphene was successfully transferred onto the hybrid structure. A piezoelectric nanogenerator is demonstrated by using the fabricated graphene/ZnO NR hybrid structure. The nanogenerator

The cancer theory of pulmonary arterial hypertension

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Boucherat, Olivier; Vitry, Geraldine; Trinh, Isabelle; Paulin, Roxane; Provencher, Steeve; Bonnet, Sebastien

2017-01-01

Pulmonary arterial hypertension (PAH) remains a mysterious killer that, like cancer, is characterized by tremendous complexity. PAH development occurs under sustained and persistent environmental stress, such as inflammation, shear stress, pseudo-hypoxia, and more. After inducing an initial death of the endothelial cells, these environmental stresses contribute with time to the development of hyper-proliferative and apoptotic resistant clone of cells including pulmonary artery smooth muscle cells, fibroblasts, and even pulmonary artery endothelial cells allowing vascular remodeling and PAH development. Molecularly, these cells exhibit many features common to cancer cells offering the opportunity to exploit therapeutic strategies used in cancer to treat PAH. In this review, we outline the signaling pathways and mechanisms described in cancer that drive PAH cells’ survival and proliferation and discuss the therapeutic potential of antineoplastic drugs in PAH. PMID:28597757

Polyvinylpyrrolidone-Capped Silver Nanoparticle Inhibits Infection of Carbapenem-Resistant Strain of Acinetobacter baumannii in the Human Pulmonary Epithelial Cell

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Vishvanath Tiwari

2017-08-01

Full Text Available Acinetobacter baumannii, an opportunistic ESKAPE pathogen, causes respiratory and urinary tract infections. Its prevalence increases gradually in the clinical setup. Pathogenicity of Acinetobacter is significantly influenced by its ability to infect and survive in human pulmonary cells. Therefore, it is important to study the infection of A. baumannii in human pulmonary host cell (A-549, monitoring surface interacting and internalized bacteria. It was found that during infection of A. baumannii, about 40% bacteria adhered to A-549, whereas 20% got internalized inside pulmonary cell and induces threefold increase in the reactive oxygen species production. We have synthesized polyvinylpyrrolidone (PVP-capped AgNPs using chemical methods and tested its efficacy against carbapenem-resistant strain of A. baumannii. PVP-capped silver nanoparticles (PVP-AgNPs (30 µM have shown antibacterial activity against carbapenem-resistant strain of A. baumannii and this concentration does not have any cytotoxic effect on the human pulmonary cell line (IC50 is 130 µM. Similarly, PVP-AgNPs treatment decreases 80% viability of intracellular bacteria, decreases adherence of A. baumannii to A-549 (40 to 2.2%, and decreases intracellular concentration (20 to 1.3% of A. baumannii. This concludes that PVP-AgNPs can be developed as a substitute for carbapenem to control the infection caused by carbapenem-resistant A. baumannii.

Idiopathic CD4 lymphocytopenia with giant cell arteritis and pulmonary mucormycosis

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Ryan A. Denu

2014-10-01

Full Text Available Idiopathic CD4 lymphocytopenia (ICL is characterized by a low CD4+ lymphocyte count in the absence of HIV or other underlying etiologies. We report a case of a 57-year old man with ICL and giant cell arteritis (GCA who developed pulmonary mucormycosis, which, to our knowledge, is the first report of these occurring in a patient with ICL. Abnormally low total lymphocyte or CD4+ cell counts occurring in patients with autoimmune disorders should alert clinicians to the possibility of ICL. Immunosuppressive treatment should be used with caution in this context.

Studies of physicochemical properties of graphite oxide and thermally exfoliated/reduced graphene oxide

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Drewniak Sabina Elżbieta

2015-12-01

Full Text Available The aim of the experimental research studies was to determine some electrical properties of graphite oxide and thermally exfoliated/reduced graphene oxide. The authors tried to interpret the obtained physicochemical results. For that purpose, both resistance measurements and investigation studies were carried out in order to characterize the samples. The resistance was measured at various temperatures in the course of composition changes of gas atmospheres (which surround the samples. The studies were also supported by such methods as: scanning electron microscopy (SEM, Raman spectroscopy (RS, atomic force microscopy (AFM and thermogravimetry (TG. Moreover, during the experiments also the elemental analyses (EA of the tested samples (graphite oxide and thermally exfoliated/reduced graphene oxide were performed.

Preparation of Graphene Sheets by Electrochemical Exfoliation of Graphite in Confined Space and Their Application in Transparent Conductive Films.

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Wang, Hui; Wei, Can; Zhu, Kaiyi; Zhang, Yu; Gong, Chunhong; Guo, Jianhui; Zhang, Jiwei; Yu, Laigui; Zhang, Jingwei

2017-10-04

A novel electrochemical exfoliation mode was established to prepare graphene sheets efficiently with potential applications in transparent conductive films. The graphite electrode was coated with paraffin to keep the electrochemical exfoliation in confined space in the presence of concentrated sodium hydroxide as the electrolyte, yielding ∼100% low-defect (the D band to G band intensity ratio, I D /I G = 0.26) graphene sheets. Furthermore, ozone was first detected with ozone test strips, and the effect of ozone on the exfoliation of graphite foil and the microstructure of the as-prepared graphene sheets was investigated. Findings indicate that upon applying a low voltage (3 V) on the graphite foil partially coated with paraffin wax that the coating can prevent the insufficiently intercalated graphite sheets from prematurely peeling off from the graphite electrode thereby affording few-layer (graphene sheets in a yield of as much as 60%. Besides, the ozone generated during the electrochemical exfoliation process plays a crucial role in the exfoliation of graphite, and the amount of defect in the as-prepared graphene sheets is dependent on electrolytic potential and electrode distance. Moreover, the graphene-based transparent conductive films prepared by simple modified vacuum filtration exhibit an excellent transparency and a low sheet resistance after being treated with NH 4 NO 3 and annealing (∼1.21 kΩ/□ at ∼72.4% transmittance).

Design of amine modified polymer dispersants for liquid-phase exfoliation of transition metal dichalcogenide nanosheets and their photodetective nanocomposites

Science.gov (United States)

Lee, Jinseong; Hahnkee Kim, Richard; Yu, Seunggun; Babu Velusamy, Dhinesh; Lee, Hyeokjung; Park, Chanho; Cho, Suk Man; Jeong, Beomjin; Sol Kang, Han; Park, Cheolmin

2017-12-01

Liquid-phase exfoliation (LPE) of transition metal dichalcogenide (TMD) nanosheets is a facile, cost-effective approach to large-area photoelectric devices including photodetectors and non-volatile memories. Non-destructive exfoliation of nanosheets using macromolecular dispersing agents is beneficial in rendering the TMD nanocomposite films suitable for mechanically flexible devices. Here, an efficient LPE of molybdenum disulfide (MoS2) with an amine modified poly(styrene-co-maleic anhydride) co-polymer (AM-PSMA) is demonstrated, wherein the maleic anhydrides were converted into maleic imides with primary amines using N-Boc-(CH2) n -NH2. The exfoliation of nanosheets was facilitated through Lewis acid-base interaction between the primary amine and transition metal. The results demonstrate that the exfoliation depends upon both the fraction of primary amines in the polymer chain and their distance from the polymer backbone. Under optimized conditions of primary amine content and its distance from the backbone, AM-PSMA gave rise to a highly concentrated MoS2 nanosheet suspension that was stable for over 10 d. Exfoliation of several other TMDs was also achieved using the optimized AM-PSMA, indicating the scope of AM-PSMA applications. Furthermore, a flexible composite film of AM-PSMA and MoS2 nanosheets fabricated by vacuum-assisted filtration showed excellent photoconductive performances including a high I on/I off ratio of 102 and a fast photocurrent switching of 300 ms.

Ionic Liquid-Modified Thermosets and Their Nanocomposites: Dispersion, Exfoliation, Degradation, and Cure

Science.gov (United States)

Throckmorton, James A.

This dissertation explores the application of a room temperature ionic liquid (RTIL) to problems in the chemistry, processing, and modification of thermosetting polymers. In particular, the solution properties and reaction chemistry of 1-ethyl-3-methyl imidazolium dicyanamide (EMIM-DCN) are applied to problems of nanoparticle dispersion and processing, graphite exfoliation, cyanate ester (CE) cure, and the environmental degradation of CEs. Nanoparticle Dispersion: Nanocomposite processing can be simplified by using the same compound as both a nanoparticle solvent and an initiator for polymerization. This dual-function molecule can be designed both for solvent potential and reaction chemistry. EMIM-DCN, previously shown by our lab to act as an epoxy initiator, is used in the synthesis of silica and acid expanded graphite composites. These composites are then characterized for particle dispersion and physical properties. Individual particle dispersion of silica nanocomposites is shown, and silica nanocomposites at low loading show individual particle dispersion and improved modulus and fracture toughness. GNP nanocomposites show a 70% increase in modulus along with a 10-order of magnitude increase in electrical conductivity at 6.5 vol%, and an electrical percolation threshold of 1.7 vol%. Direct Graphite Exfoliation By Laminar Shear: This work presents a laminar-shear alternative to chemical processing and chaotic flow-fields for the direct exfoliation of graphite and the single-pot preparation of nanocomposites. Additionally, we develop the theory of laminar flow through a 3-roll mill, and apply that theory to the latest developments in the theory of graphite interlayer shear. The resulting nanocomposite shows low electrical percolation (0.5 vol%) and low thickness (1-3 layer) graphite/graphene flakes. Additionally, the effect of processing conditions by rheometry and comparison with solvent-free conditions reveal the interactions between processing and matrix

Role of human pulmonary fibroblast-derived MCP-1 in cell activation and migration in experimental silicosis

International Nuclear Information System (INIS)

Liu, Xueting; Fang, Shencun; Liu, Haijun; Wang, Xingang; Dai, Xiaoniu; Yin, Qing; Yun, Tianwei; Wang, Wei; Zhang, Yingming; Liao, Hong; Zhang, Wei; Yao, Honghong; Chao, Jie

2015-01-01

Background: Silicosis is a systemic disease caused by inhaling silicon dioxide (SiO 2 ). Phagocytosis of SiO 2 in the lung initiates an inflammatory cascade that results in fibroblast proliferation and migration and subsequent fibrosis. Clinical evidence indicates that the activation of alveolar macrophages by SiO 2 produces rapid and sustained inflammation that is characterized by the generation of monocyte chemotactic protein 1 (MCP-1), which induces fibrosis. Pulmonary fibroblast-derived MCP-1 may play a critical role in fibroblast proliferation and migration. Methods and results: Experiments using primary cultured adult human pulmonary fibroblasts (HPF-a) demonstrated the following results: 1) SiO 2 treatment resulted in the rapid and sustained induction of MCP-1 as well as the elevation of the CC chemokine receptor type 2 (CCR2) protein levels; 2) pretreatment of HPF-a with RS-102895, a specific CCR2 inhibitor, abolished the SiO 2 -induced increase in cell activation and migration in both 2D and 3D culture systems; and 3) RNA interference targeting CCR2 prevented the SiO 2 -induced increase in cell migration. Conclusion: These data demonstrated that the up-regulation of pulmonary fibroblast-derived MCP-1 is involved in pulmonary fibroblast migration induced by SiO 2 . CCR2 was also up-regulated in response to SiO 2 , and this up-regulation facilitated the effect of MCP-1 on fibroblasts. Our study deciphered the link between fibroblast-derived MCP-1 and SiO 2 -induced cell migration. This finding provides novel insight into the potential of MCP-1 in the development of novel therapeutic strategies for silicosis. - Highlights: • Role of pulmonary fibroblast-derived MCP-1 in experimental silicosis was studied. • SiO 2 induced MCP-1 release from cultured human pulmonary fibroblast (HPF-a). • SiO 2 directly activated HPF-a via the MCP-1/CCR2 pathway. • SiO 2 increased HPF-a migration in both 2D and 3D model via the MCP-1/CCR2 pathway. • RNA-i of MCP-1/CCR2

Role of human pulmonary fibroblast-derived MCP-1 in cell activation and migration in experimental silicosis

Energy Technology Data Exchange (ETDEWEB)

Liu, Xueting [Department of Physiology, Medical School of Southeast University, Nanjing, Jiangsu 210009 (China); Fang, Shencun [Nine Department of Respiratory Medicine, Nanjing Chest Hospital, Nanjing, Jiangsu 210029 (China); Liu, Haijun [Neurobiology Laboratory, New Drug Screening Centre, China Pharmaceutical University, Nanjing, Jiangsu 210009 (China); Wang, Xingang; Dai, Xiaoniu; Yin, Qing; Yun, Tianwei [Department of Physiology, Medical School of Southeast University, Nanjing, Jiangsu 210009 (China); Wang, Wei; Zhang, Yingming [Nine Department of Respiratory Medicine, Nanjing Chest Hospital, Nanjing, Jiangsu 210029 (China); Liao, Hong [Neurobiology Laboratory, New Drug Screening Centre, China Pharmaceutical University, Nanjing, Jiangsu 210009 (China); Zhang, Wei [Department of Physiology, Medical School of Southeast University, Nanjing, Jiangsu 210009 (China); Yao, Honghong [Department of Pharmacology, Medical School of Southeast University, Nanjing, Jiangsu 210009 (China); Chao, Jie, E-mail: chaojie@seu.edu.cn [Department of Physiology, Medical School of Southeast University, Nanjing, Jiangsu 210009 (China)

2015-10-15

Background: Silicosis is a systemic disease caused by inhaling silicon dioxide (SiO{sub 2}). Phagocytosis of SiO{sub 2} in the lung initiates an inflammatory cascade that results in fibroblast proliferation and migration and subsequent fibrosis. Clinical evidence indicates that the activation of alveolar macrophages by SiO{sub 2} produces rapid and sustained inflammation that is characterized by the generation of monocyte chemotactic protein 1 (MCP-1), which induces fibrosis. Pulmonary fibroblast-derived MCP-1 may play a critical role in fibroblast proliferation and migration. Methods and results: Experiments using primary cultured adult human pulmonary fibroblasts (HPF-a) demonstrated the following results: 1) SiO{sub 2} treatment resulted in the rapid and sustained induction of MCP-1 as well as the elevation of the CC chemokine receptor type 2 (CCR2) protein levels; 2) pretreatment of HPF-a with RS-102895, a specific CCR2 inhibitor, abolished the SiO{sub 2}-induced increase in cell activation and migration in both 2D and 3D culture systems; and 3) RNA interference targeting CCR2 prevented the SiO{sub 2}-induced increase in cell migration. Conclusion: These data demonstrated that the up-regulation of pulmonary fibroblast-derived MCP-1 is involved in pulmonary fibroblast migration induced by SiO{sub 2}. CCR2 was also up-regulated in response to SiO{sub 2}, and this up-regulation facilitated the effect of MCP-1 on fibroblasts. Our study deciphered the link between fibroblast-derived MCP-1 and SiO{sub 2}-induced cell migration. This finding provides novel insight into the potential of MCP-1 in the development of novel therapeutic strategies for silicosis. - Highlights: • Role of pulmonary fibroblast-derived MCP-1 in experimental silicosis was studied. • SiO{sub 2} induced MCP-1 release from cultured human pulmonary fibroblast (HPF-a). • SiO{sub 2} directly activated HPF-a via the MCP-1/CCR2 pathway. • SiO{sub 2} increased HPF-a migration in both 2D and 3D

Soluble, Exfoliated Two-Dimensional Nanosheets as Excellent Aqueous Lubricants.

Science.gov (United States)

Zhang, Wenling; Cao, Yanlin; Tian, Pengyi; Guo, Fei; Tian, Yu; Zheng, Wen; Ji, Xuqiang; Liu, Jingquan

2016-11-30

Dispersion in water of two-dimensional (2D) nanosheets is conducive to their practical applications in fundamental science communities due to their abundance, low cost, and ecofriendliness. However, it is difficult to achieve stable aqueous 2D material suspensions because of the intrinsic hydrophobic properties of the layered materials. Here, we report an effective and economic way of producing various 2D nanosheets (h-BN, MoS 2 , MoSe 2 , WS 2 , and graphene) as aqueous dispersions using carbon quantum dots (CQDs) as exfoliation agents and stabilizers. The dispersion was prepared through a liquid phase exfoliation. The as-synthesized stable 2D nanosheets based dispersions were characterized by UV-vis, HRTEM, AFM, Raman, XPS, and XRD. The solutions based on CQD decorated 2D nanosheets were utilized as aqueous lubricants, which realized a friction coefficient as low as 0.02 and even achieved a superlubricity under certain working conditions. The excellent lubricating properties were attributed to the synergetic effects of the 2D nanosheets and CQDs, such as good dispersion stability and easy-sliding interlayer structure. This work thus proposes a novel strategy for the design and preparation of high-performance water based green lubricants.

Protein S is protective in pulmonary fibrosis.

Science.gov (United States)

Urawa, M; Kobayashi, T; D'Alessandro-Gabazza, C N; Fujimoto, H; Toda, M; Roeen, Z; Hinneh, J A; Yasuma, T; Takei, Y; Taguchi, O; Gabazza, E C

2016-08-01

Essentials Epithelial cell apoptosis is critical in the pathogenesis of idiopathic pulmonary fibrosis. Protein S, a circulating anticoagulant, inhibited apoptosis of lung epithelial cells. Overexpression of protein S in lung cells reduced bleomycin-induced pulmonary fibrosis. Intranasal therapy with exogenous protein S ameliorated bleomycin-induced pulmonary fibrosis. Background Pulmonary fibrosis is the terminal stage of interstitial lung diseases, some of them being incurable and of unknown etiology. Apoptosis plays a critical role in lung fibrogenesis. Protein S is a plasma anticoagulant with potent antiapoptotic activity. The role of protein S in pulmonary fibrosis is unknown. Objectives To evaluate the clinical relevance of protein S and its protective role in pulmonary fibrosis. Methods and Results The circulating level of protein S was measured in patients with pulmonary fibrosis and controls by the use of enzyme immunoassays. Pulmonary fibrosis was induced with bleomycin in transgenic mice overexpressing human protein S and wild-type mice, and exogenous protein S or vehicle was administered to wild-type mice; fibrosis was then compared in both models. Patients with pulmonary fibrosis had reduced circulating levels of protein S as compared with controls. Inflammatory changes, the levels of profibrotic cytokines, fibrosis score, hydroxyproline content in the lungs and oxygen desaturation were significantly reduced in protein S-transgenic mice as compared with wild-type mice. Wild-type mice treated with exogenous protein S showed significant decreases in the levels of inflammatory and profibrotic markers and fibrosis in the lungs as compared with untreated control mice. After bleomycin infusion, mice overexpressing human protein S showed significantly low caspase-3 activity, enhanced expression of antiapoptotic molecules and enhanced Akt and Axl kinase phosphorylation as compared with wild-type counterparts. Protein S also inhibited apoptosis of alveolar

Effects of bone marrow-derived cells on monocrotaline- and hypoxia-induced pulmonary hypertension in mice

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Vainchenker William

2007-01-01

Full Text Available Abstract Background Bone marrow -derived cells (BMDCs can either limit or contribute to the process of pulmonary vascular remodeling. Whether the difference in their effects depends on the mechanism of pulmonary hypertension (PH remains unknown. Objectives We investigated the effect of BMDCs on PH induced in mice by either monocrotaline or exposure to chronic hypoxia. Methods Intravenous administration of the active monocrotaline metabolite (monocrotaline pyrrole, MCTp to C57BL/6 mice induced PH within 15 days, due to remodeling of small distal vessels. Three days after the MCTp injection, the mice were injected with BMDCs harvested from femurs and tibias of donor mice treated with 5-fluorouracil (3.5 mg IP/animal to deplete mature cells and to allow proliferation of progenitor cells. Results BMDCs significantly attenuated PH as assessed by reductions in right ventricular systolic pressure (20 ± 1 mmHg vs. 27 ± 1 mmHg, P ≤ 0.01, right ventricle weight/left ventricle+septum weight ratio (0.29 ± 0.02 vs. 0.36 ± 0.01, P ≤ 0.03, and percentage of muscularized vessels (26.4% vs. 33.5%, P ≤ 0.05, compared to control animals treated with irradiated BMDCs. Tracking cells from constitutive GFP-expressing male donor mice with anti-GFP antibodies or chromosome Y level measurement by quantitative real-time PCR showed BMDCs in the lung. In contrast, chronically hypoxic mice subjected to the same procedure failed to show improvement in PH. Conclusion These results show that BMDCs limit pulmonary vascular remodeling induced by vascular injury but not by hypoxia.

Direct synthesis of hydrophobic graphene-based nanosheets via chemical modification of exfoliated graphene oxide.

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Wang, Jigang; Wang, Yongsheng; He, Dawei; Liu, Zhiyong; Wu, Hongpeng; Wang, Haiteng; Zhao, Yu; Zhang, Hui; Yang, Bingyang; Xu, Haiteng; Fu, Ming

2012-08-01

Hydrophobic graphene-based material at the nanoscale was prepared by treatment of exfoliated graphene oxide with organic isocyanates. The lipophilic modified graphene oxide (LMGO) can then be exfoliated into the functionalized graphene nanoplatelets that can form a stable dispersion in polar aprotic solvents. AFM image shows the thickness of LMGO is approximately 1 nm. Characterization of LMGO by elemental analysis suggested that the chemical treatment results in the functionalization of the carboxyl and hydroxyl groups in GO via formation of amides and carbamate esters, respectively. The degree of GO functionalization can be controlled via either the reactivity of the isocyanate or the reaction time. Then we investigated the thermal properties of the SPFGraphene by using thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC), the TGA curve shows a greater weight loss of approximately 20% occurred indicating removal of functional groups from the LMGO sheets and an obvious exothermic peak at 176 degrees can be observed from 150 to 250 degrees. We also compared the structure of graphene oxide with the structure of chemical treated graphene oxide by FT-IR spectroscopy. The morphology and microstructure of the LMGO nanosheets were also characterized by SEM and XRD. Graphene can be used to fabricate a wide range of simple electronic devices such as field-effect transistors, resonators, quantum dots and some other extensive industrial manufacture such as super capacitor, li ion battery, solar cells and even transparent electrodes in device applications.

Behaviour of the surface hydroxide groups of exfoliated kaolinite in the gas phase and during water adsorption.

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Táborosi, Attila; Szilágyi, Róbert K

2016-02-14

The chemical and physical properties, and thus the reactivity of phylloaluminosilicates can be tailored by intercalation, delamination, and exfoliation processes. In going from the periodic crystalline to the molecular exfoliated phase, surface defects and modifications gain importance as each face of the phylloaluminosilicate comes in direct contact with the external chemical environment. In this work, we extend our earlier studies on the molecular cluster modelling of exfoliated kaolinite sheets by evaluating the positions and orientations of surface hydroxide groups and bridging oxide anions, as the sites of reactivity. The previous focus on the inner chemical environment of a single kaolinite layer is shifted to the surface exposed octahedral aluminium-hydroxide and tetrahedral silicon-oxide sheets. The combination of semi-empirical, ab initio wave function, and density functional calculations unanimously support the amphoteric nature of the surface hydroxide groups with respect to H-bonding donor/acceptor capabilities. To a lesser extent, we observe the same for the bridging oxide anions. This is in contrast to the crystalline phase, which manifests only donor orientation for maintaining an inter-layer H-bond network. These results suggest that both electrophilic and nucleophilic characteristics of the octahedral and tetrahedral sheets need to be considered during intercalation and concomitant exfoliation of the kaolinite sheets.

Electrical bistabilities and memory mechanisms of nonvolatile organic bistable devices based on exfoliated muscovite-type mica nanoparticle/poly(methylmethacrylate) nanocomposites

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Lim, Won Gyu; Lee, Dea Uk; Na, Han Gil; Kim, Hyoun Woo; Kim, Tae Whan

2018-02-01

Organic bistable devices (OBDs) with exfoliated mica nanoparticles (NPs) embedded into an insulating poly(methylmethacrylate) (PMMA) layer were fabricated by using a spin-coating method. Current-voltage (I-V) curves for the Al/PMMA/exfoliated mica NP/PMMA/indium-tin-oxide/glass devices at 300 K showed a clockwise current hysteresis behavior due to the existence of the exfoliated muscovite-type mica NPs, which is an essential feature for bistable devices. Write-read-erase-read data showed that the OBDs had rewritable nonvolatile memories and an endurance number of ON/OFF switching for the OBDs of 102 cycles. An ON/OFF ratio of 1 × 103 was maintained for retention times larger than 1 × 104 s. The memory mechanisms of the fabricated OBDs were described by using the trapping and the tunneling processes within a PMMA active layer containing exfoliated muscovite-type mica NPs on the basis of the energy band diagram and the I-V curves.

Successful treatment with carboplatin and nanoparticle albumin-bound paclitaxel in a patient with pulmonary spindle cell carcinoma

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Takahiro Tsuji

2015-01-01

Discussion: Preclinical models suggested that nab-PTX may reach the tumor microenvironment more efficiently than solvent-based paclitaxel (sb-PTX and be preferentially taken up by cancer cells. Considering that there is no effective treatment for patients with pulmonary SpCC, nab-PTX may merit further investigation in patients with pulmonary SpCC.

Mechanistic examination of pre-exfoliating confinement of surface-active polystyrene nanobeads within pristine clay.

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Khvan, Svetlana; Kim, Junkyung; Lee, Sang-Soo

2007-02-01

Hydrophobic polymer (PS) nanoparticles preformed through an emulsifier-free emulsion polymerization method were successfully incorporated into a gallery of pristine sodium montmorillonite via interfacial cation exchange. The polymer beads confined between clay nanosheets were capable of (1) preventing the silicate layers from restacking and (2) maintaining the exfoliated state of clay. The increase in the abundance of surface groups promoted adsorption of the nanobeads onto the silicate surface and eventually led to the establishment of strong polymer-clay interactions. These findings suggest that, on the basis of the obtained pre-exfoliated clay masterbatch, the presence of strong polymer-clay interactions could improve the mechanical performance of nanocomposites.

Supercritical fluid extraction of bi & multi-layer graphene sheets from graphite by using exfoliation technique

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Xavier, Gauravi; Dave, Bhoomi; Khanna, Sakshum

2018-05-01

In recent times, researchers have turned to explore the possibility of using Supercritical Fluid (SCFs) system to penetrate into the inert-gaping of graphite and exfoliate it into a number of layer graphene sheets. The supercritical fluid holds excellent wetting surfaces with low interfacial tension and high diffusion coefficients. Although SCFs exfoliation approach looks promising to developed large scale & low-cost graphene sheet but has not received much attention. To arouse interest and reflection on this approach, this review is organized to summarize the recent progress in graphene production by SCF technology. Here we present the simplest route to obtained layers of graphene sheets by intercalating and exfoliating graphite using supercritical CO2 processing. The layers graphene nano-sheets were collected in dichloromethane (DCM) solution which prevents the restocking of sheets. The obtained graphene sheets show the desired characteristics and thus can be used in physical, chemical and biological sciences. Thus this method provides an effortless and eco-friendly approach for the synthesis of layers of graphene sheets.

Ex situ integration of iron oxide nanoparticles onto the exfoliated expanded graphite flakes in water suspension

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Jović Nataša

2014-01-01

Full Text Available Hybrid structures composed of exfoliated expanded graphite (EG and iron oxide nanocrystals have been produced by an ex situ process. The iron oxide nanoparticles coated with meso-2,3-dimercaptosuccinic acid (DMSA, or poly(acrylic acid (PAA were integrated onto the exfoliated EG flakes by mixing their aqueous suspensions at room temperature under support of 1-ethyl-3-(3-dimethylaminopropylcarbodiimide (EDC and N-hydroxysuccin-nimide (NHS. EG flakes have been used both, naked and functionalized with branched polyethylenimine (PEI. Complete integration of two constituents has been achieved and mainteined stable for more than 12 months. No preferential spatial distribution of anchoring sites for attachement of iron oxide nanoparticles has been observed, regardless EG flakes have been used naked or functionalized with PEI molecules. The structural and physico-chemical characteristics of the exfoliated expanded graphite and its hybrids nanostructures has been investigated by SEM, TEM, FTIR and Raman techniques. [Projekat Ministarstva nauke Republike Srbije, br. 45015

Exfoliation and van der Waals heterostructure assembly of intercalated ferromagnet Cr1/3TaS2

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Yamasaki, Yuji; Moriya, Rai; Arai, Miho; Masubuchi, Satoru; Pyon, Sunseng; Tamegai, Tsuyoshi; Ueno, Keiji; Machida, Tomoki

2017-12-01

Ferromagnetic van der Waals (vdW) materials are in demand for spintronic devices with all-two-dimensional-materials heterostructures. Here, we demonstrate mechanical exfoliation of magnetic-atom-intercalated transition metal dichalcogenide Cr1/3TaS2 from its bulk crystal; previously such intercalated materials were thought difficult to exfoliate. Magnetotransport in exfoliated tens-of-nanometres-thick flakes revealed ferromagnetic ordering below its Curie temperature T C ~ 110 K as well as strong in-plane magnetic anisotropy; these are identical to its bulk properties. Further, van der Waals heterostructure assembly of Cr1/3TaS2 with another intercalated ferromagnet Fe1/4TaS2 is demonstrated using a dry-transfer method. The fabricated heterojunction composed of Cr1/3TaS2 and Fe1/4TaS2 with a native Ta2O5 oxide tunnel barrier in between exhibits tunnel magnetoresistance (TMR), revealing possible spin injection and detection with these exfoliatable ferromagnetic materials through the vdW junction.

DNA Damage and Pulmonary Hypertension

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Ranchoux, Benoît; Meloche, Jolyane; Paulin, Roxane; Boucherat, Olivier; Provencher, Steeve; Bonnet, Sébastien

2016-01-01

Pulmonary hypertension (PH) is defined by a mean pulmonary arterial pressure over 25 mmHg at rest and is diagnosed by right heart catheterization. Among the different groups of PH, pulmonary arterial hypertension (PAH) is characterized by a progressive obstruction of distal pulmonary arteries, related to endothelial cell dysfunction and vascular cell proliferation, which leads to an increased pulmonary vascular resistance, right ventricular hypertrophy, and right heart failure. Although the primary trigger of PAH remains unknown, oxidative stress and inflammation have been shown to play a key role in the development and progression of vascular remodeling. These factors are known to increase DNA damage that might favor the emergence of the proliferative and apoptosis-resistant phenotype observed in PAH vascular cells. High levels of DNA damage were reported to occur in PAH lungs and remodeled arteries as well as in animal models of PH. Moreover, recent studies have demonstrated that impaired DNA-response mechanisms may lead to an increased mutagen sensitivity in PAH patients. Finally, PAH was linked with decreased breast cancer 1 protein (BRCA1) and DNA topoisomerase 2-binding protein 1 (TopBP1) expression, both involved in maintaining genome integrity. This review aims to provide an overview of recent evidence of DNA damage and DNA repair deficiency and their implication in PAH pathogenesis. PMID:27338373

Intravascular pulmonary metastases

International Nuclear Information System (INIS)

Shepard, J.A.O.; Moore, E.H.; Templeton, P.A.; McLoud, T.C.

1988-01-01

The diagnosis of intravascular metastatic tumor emboli to the lungs is rarely made. The authors present a characteristic radiographic finding of intravascular lung metastases that they observed in four patients with diagnoses or right atrial myoxoma, invasive renal cell carcinoma, invasive pelvic osteosarcoma, and recurrent pelvic chondrosarcoma. Substantiation of intravascular pulmonary metastases was achieved by means of autopsy, pulmonary artery biopsy, and surgical documentation of tumor invasion of the inferior vena cava or pelvic veins. In all four cases, chest computed tomography (CT) demonstrated branching, beaded opacities extending from the hila into the periphery of the lung in the distribution of pulmonary arteries. In one case, similar findings were observed in magnetic resonance (MR) images of the chest. Follow-up studies in three cases showed progressive enlargement and varicosity of the abnormal pulmonary artery consistent with proliferation of intravascular tumor. In the case of metastatic osteosarcoma, intraluminal ossification was also observed at CT. In three of four cases, pulmonary infarction was demonstrated in the distribution of the abnormal pulmonary arteries seen at CT as small, peripheral, wedge-shaped opacities. The demonstration of progressively dilated and beaded pulmonary arteries in patients with extrathoracic malignancies is suggestive of intravascular lung metastases, particularly when accompanied by peripheral infarction

Regeneration of alveolar type I and II cells from Scgb1a1-expressing cells following severe pulmonary damage induced by bleomycin and influenza.

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Dahai Zheng

Full Text Available The lung comprises an extensive surface of epithelia constantly exposed to environmental insults. Maintaining the integrity of the alveolar epithelia is critical for lung function and gaseous exchange. However, following severe pulmonary damage, what progenitor cells give rise to alveolar type I and II cells during the regeneration of alveolar epithelia has not been fully determined. In this study, we have investigated this issue by using transgenic mice in which Scgb1a1-expressing cells and their progeny can be genetically labeled with EGFP. We show that following severe alveolar damage induced either by bleomycin or by infection with influenza virus, the majority of the newly generated alveolar type II cells in the damaged parenchyma were labeled with EGFP. A large proportion of EGFP-expressing type I cells were also observed among the type II cells. These findings strongly suggest that Scgb1a1-expressing cells, most likely Clara cells, are a major cell type that gives rise to alveolar type I and II cells during the regeneration of alveolar epithelia in response to severe pulmonary damage in mice.

Baicalin inhibits hypoxia-induced pulmonary artery smooth muscle cell proliferation via the AKT/HIF-1α/p27-associated pathway.

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Zhang, Lin; Pu, Zhichen; Wang, Junsong; Zhang, Zhifeng; Hu, Dongmei; Wang, Junjie

2014-05-09

Baicalin, a flavonoid compound purified from the dry roots of Scutellaria baicalensis Georgi, has been shown to possess various pharmacological actions. Previous studies have revealed that baicalin inhibits the growth of cancer cells through the induction of apoptosis. Pulmonary arterial hypertension (PAH) is a devastating disease characterized by enhanced pulmonary artery smooth muscle cell (PASMCs) proliferation and suppressed apoptosis. However, the potential mechanism of baicalin in the regulation of PASMC proliferation and the prevention of cardiovascular diseases remains unexplored. To test the effects of baicalin on hypoxia, we used rats treated with or without baicalin (100 mg·kg⁻¹ each rat) at the beginning of the third week after hypoxia. Hemodynamic and pulmonary pathomorphology data showed that right ventricular systolic pressures (RVSP), the weight of the right ventricle/left ventricle plus septum (RV/LV + S) ratio and the medial width of pulmonary arterioles were much higher in chronic hypoxia. However, baicalin treatment repressed the elevation of RVSP, RV/LV + S and attenuated the pulmonary vascular structure remodeling (PVSR) of pulmonary arterioles induced by chronic hypoxia. Additionally, baicalin (10 and 20 μmol·L⁻¹) treatment suppressed the proliferation of PASMCs and attenuated the expression of hypoxia-inducible factor-α (HIF-α) under hypoxia exposure. Meanwhile, baicalin reversed the hypoxia-induced reduction of p27 and increased AKT/protein kinase B phosphorylation p-AKT both in vivo and in vitro. These results suggested that baicalin could effectively attenuate PVSR and hypoxic pulmonary hypertension.

Aerosolized liposomes with dipalmitoyl phosphatidylcholine enhance pulmonary insulin delivery.

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Chono, Sumio; Fukuchi, Rie; Seki, Toshinobu; Morimoto, Kazuhiro

2009-07-20

The pulmonary insulin delivery characteristics of liposomes were examined. Aerosolized liposomes containing insulin were administered into rat lungs and the enhancing effect on insulin delivery was evaluated by changes of plasma glucose levels. Liposomes with dipalmitoyl phosphatidylcholine (DPPC) enhanced pulmonary insulin delivery in rats, however, liposomes with dilauroyl, dimyristoyl, distearoyl or dioleoyl phosphatidylcholine did not. Liposomes with DPPC also enhanced the in vitro permeation of FITC dextran (Mw 4400, FD-4) through the calu-3 cell monolayer by reducing the transepithelial electrical resistance and did not harm lung tissues in rats. These findings suggest that liposomes with DPPC enhance pulmonary insulin delivery by opening the epithelial cell space in the pulmonary mucosa not mucosal cell damage. Liposomes with DPPC could be useful as a pulmonary delivery system for peptide and protein drugs.

Sulfuric acid intercalated-mechanical exfoliation of reduced graphene oxide from old coconut shell

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Islamiyah, Wildatun; Nashirudin, Luthfi; Baqiya, Malik A.; Cahyono, Yoyok; Darminto

2018-04-01

We report a fecile preparation of reduced grapheme oxide (rGO) from an old coconut shell by rapid reduction of heating at 400°C, chemical exfoliation using H2SO4 and HCl intercalating and mechanical exfoliation using ultrasonication. The produced samples consist of random stacks of nanometer-sized sheets. The dispersions prepared from H2SO4 had broader size distributions and larger particle sizes than the that from HCl. An average size of rGO in H2SO4 and HCl is respectively 23.62 nm and 570.4 nm. Furthermore, sample prepared in H2SO4 exhibited a high electronical conductivity of 1.1 × 10-3 S/m with a low energy gap of 0.11 eV.

Thermal monitoring of a granitic exfoliation sheet and cliff in Yosemite Valley, California (USA)

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Guerin, Antoine; Matasci, Battista; Collins, Brian D.; Stock, Greg M.; Derron, Marc-Henri; Jaboyedoff, Michel

2015-04-01

In recent years, new remote sensing techniques such as Terrestrial Laser Scanner (TLS) and Infrared Thermography (IRT) have been used in parallel for rock weathering and weakness detection in slope stability analysis. Nevertheless, the effects of thermal stresses on rock face deformation are still poorly quantified, especially for steep and inaccessible cliffs. To better understand how daily temperature fluctuations influence the behavior of exfoliation joints (i.e., fractures separating exfoliation sheets), we monitored a granitic exfoliation sheet in detail using TLS and IRT over a several day period and also compiled a single TLS-IRT thermal panorama of a larger nearby granitic cliff composed of hundreds to thousands of similar exfoliation sheets. The exfoliation sheet had been previously instrumented for 3.5 years beginning in May 2010 using crackmeters and temperature sensors (Collins and Stock, 2010 and 2012), thereby providing an important baseline to compare our IRT measurements. For several consecutive days, a series of infrared thermal images (collected every 20 min.) of the exfoliation flake (19 m by 4 m by 0.1 m) was taken with a long range IRISYS IRI 4040 thermal imager, as well as several ground-based LiDAR scans, collected at 4 mm point spacing. These pictures were draped on the TLS triangular meshes to quantify the lateral propagation of temperature during the warming and cooling periods. The evolution of vertical and horizontal temperature profiles was also investigated. Results show that the sheet edge undergoes the most significant temperature changes and that warming takes place from the inside part to the border of the flake; conversely cooling takes place from the outside-inwards. Furthermore, the comparison of point clouds indicates a maximum crack aperture of over 1 cm occurring in the afternoon (12:00 to 15:00), when temperatures are at their maximum. The thermal panoramic image of the cliff (600 m wide by 300 m tall) was created using over

Non-isothermal cure and exfoliation of tri-functional epoxy-clay nanocomposites

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F. Shiravand

2015-08-01

Full Text Available The non-isothermal cure kinetics of polymer silicate layered nanocomposites based on a tri-functional epoxy resin has been investigated by differential scanning calorimetry. From an analysis of the kinetics as a function of the clay content, it can be concluded that the non-isothermal cure reaction can be considered to consist of four different processes: the reaction of epoxy groups with the diamine curing agent; an intra-gallery homopolymerisation reaction which occurs concurrently with the epoxy-amine reaction; and two extra-gallery homopolymerisation reactions, catalysed by the onium ion of the organically modified clay and by the tertiary amines resulting from the epoxy-amine reaction. The final nanostructure displays a similar quality of exfoliation as that observed for the isothermal cure of the same nanocomposite system. This implies that the intra-gallery reaction, which is responsible for the exfoliation, is not significantly inhibited by the extra-gallery epoxy-amine cross-linking reaction.

Detection of survivin, carcinoembryonic antigen and ErbB2 level in oral squamous cell carcinoma patients.

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Li, Shu-Xia; Yang, Yan-Qi; Jin, Li-Jian; Cai, Zhi-Gang; Sun, Zheng

2016-01-01

The aim of this study was to detect the survivin, carcinoembryonic antigen (CEA) and ErbB2 in the saliva, serum and local tumor-exfoliated cells of oral squamous cell carcinoma (OSCC) patients, for providing reliable tumor markers for the early detection of oral malignant cancer. The saliva, serum, and local tumor-exfoliated cell samples of 26 OSCC patients without chemotherapy and 10 non-cancer patients were collected in Department of Oral and Maxillofacial Surgery, School of Stomatology, Peking University. The contents of survivin, CEA and ErbB2 using were detected usingenzyme-linked immunosorbent assay. The survivin and CEA levels in saliva and local tumor-exfoliated cells of OSCC patients were significantly higher than those in the non-cancer patients (P oral malignant cancer.

Pulmonary heart valve replacement using stabilized acellular xenogeneic scaffolds; effects of seeding with autologous stem cells

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Harpa Marius Mihai

2015-12-01

Full Text Available Background: We hypothesized that an ideal heart valve replacement would be acellular valve root scaffolds seeded with autologous stem cells. To test this hypothesis, we prepared porcine acellular pulmonary valves, seeded them with autologous adipose derived stem cells (ADSCs and implanted them in sheep and compared them to acellular valves.

The Role of Immune and Inflammatory Cells in Idiopathic Pulmonary Fibrosis.

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Desai, Omkar; Winkler, Julia; Minasyan, Maksym; Herzog, Erica L

2018-01-01

The contribution of the immune system to idiopathic pulmonary fibrosis (IPF) remains poorly understood. While most sources agree that IPF does not result from a primary immunopathogenic mechanism, evidence gleaned from animal modeling and human studies suggests that innate and adaptive immune processes can orchestrate existing fibrotic responses. This review will synthesize the available data regarding the complex role of professional immune cells in IPF. The role of innate immune populations such as monocytes, macrophages, myeloid suppressor cells, and innate lymphoid cells will be discussed, as will the activation of these cells via pathogen-associated molecular patterns derived from invading or commensural microbes, and danger-associated molecular patterns derived from injured cells and tissues. The contribution of adaptive immune responses driven by T-helper cells and B cells will be reviewed as well. Each form of immune activation will be discussed in the context of its relationship to environmental and genetic factors, disease outcomes, and potential therapies. We conclude with discussion of unanswered questions and opportunities for future study in this area.

The Role of Immune and Inflammatory Cells in Idiopathic Pulmonary Fibrosis

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Omkar Desai

2018-03-01

Full Text Available The contribution of the immune system to idiopathic pulmonary fibrosis (IPF remains poorly understood. While most sources agree that IPF does not result from a primary immunopathogenic mechanism, evidence gleaned from animal modeling and human studies suggests that innate and adaptive immune processes can orchestrate existing fibrotic responses. This review will synthesize the available data regarding the complex role of professional immune cells in IPF. The role of innate immune populations such as monocytes, macrophages, myeloid suppressor cells, and innate lymphoid cells will be discussed, as will the activation of these cells via pathogen-associated molecular patterns derived from invading or commensural microbes, and danger-associated molecular patterns derived from injured cells and tissues. The contribution of adaptive immune responses driven by T-helper cells and B cells will be reviewed as well. Each form of immune activation will be discussed in the context of its relationship to environmental and genetic factors, disease outcomes, and potential therapies. We conclude with discussion of unanswered questions and opportunities for future study in this area.

The Role of Immune and Inflammatory Cells in Idiopathic Pulmonary Fibrosis

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Desai, Omkar; Winkler, Julia; Minasyan, Maksym; Herzog, Erica L.

2018-01-01

The contribution of the immune system to idiopathic pulmonary fibrosis (IPF) remains poorly understood. While most sources agree that IPF does not result from a primary immunopathogenic mechanism, evidence gleaned from animal modeling and human studies suggests that innate and adaptive immune processes can orchestrate existing fibrotic responses. This review will synthesize the available data regarding the complex role of professional immune cells in IPF. The role of innate immune populations such as monocytes, macrophages, myeloid suppressor cells, and innate lymphoid cells will be discussed, as will the activation of these cells via pathogen-associated molecular patterns derived from invading or commensural microbes, and danger-associated molecular patterns derived from injured cells and tissues. The contribution of adaptive immune responses driven by T-helper cells and B cells will be reviewed as well. Each form of immune activation will be discussed in the context of its relationship to environmental and genetic factors, disease outcomes, and potential therapies. We conclude with discussion of unanswered questions and opportunities for future study in this area. PMID:29616220

Studies on incorporation of exfoliated bentonitic clays in polyurethane foams for increasing flame retardancy

International Nuclear Information System (INIS)

Quagliano, J; García, Irma Gavilán

2012-01-01

In this contribution we report the results of studying the incorporation of exfoliated bentonitic clays into polyurethane foams. A suspension in water of a sodium bentonite from Argentine Patagonia was interchanged with cetyl trimethyl ammonium bromide (CTAB) for 4 h at 80°C, rendering an exfoliated clay, which is nanometric in only one dimension. This nanoclay, when dispersed in the polyurethane, resulted in the same fire retardancy rating (UL-94) than when polyurethane was treated with a commercial nanoclay. Scanning electron microscopy (SEM) at low augmentations of polyurethane samples treated with the synthethized nanoclay (2,5% w/w) showed no differences respect to untreated polyurethane, except for the irregularity of void edges.

Beneficial Effects of Renal Denervation on Pulmonary Vascular Remodeling in Experimental Pulmonary Artery Hypertension.

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Qingyan, Zhao; Xuejun, Jiang; Yanhong, Tang; Zixuan, Dai; Xiaozhan, Wang; Xule, Wang; Zongwen, Guo; Wei, Hu; Shengbo, Yu; Congxin, Huang

2015-07-01

Activation of both the sympathetic nervous system and the renin-angiotensin-aldosterone system is closely associated with pulmonary arterial hypertension. We hypothesized that renal denervation decreases renin-angiotensin-aldosterone activity and inhibits the progression of pulmonary arterial hypertension. Twenty-two beagles were randomized into 3 groups. The dogs' pulmonary dynamics were measured before and 8 weeks after injection of 0.1mL/kg dimethylformamide (control dogs) or 2mg/kg dehydromonocrotaline (pulmonary arterial hypertension and pulmonary arterial hypertension + renal denervation dogs). Eight weeks after injection, neurohormone levels and pulmonary tissue morphology were measured. Levels of plasma angiotensin II and endothelin-1 were significantly increased after 8 weeks in the pulmonary arterial hypertension dogs and were higher in the lung tissues of these dogs than in those of the control and renal denervation dogs (mean [standard deviation] angiotensin II: 65 [9.8] vs 38 [6.7], 46 [8.1]; endothelin-1: 96 [10.3] vs 54 [6.2], 67 [9.4]; P < .01). Dehydromonocrotaline increased the mean pulmonary arterial pressure (16 [3.4] mmHg vs 33 [7.3] mmHg; P < .01), and renal denervation prevented this increase. Pulmonary smooth muscle cell proliferation was higher in the pulmonary arterial hypertension dogs than in the control and pulmonary arterial hypertension + renal denervation dogs. Renal denervation attenuates pulmonary vascular remodeling and decreases pulmonary arterial pressure in experimental pulmonary arterial hypertension. The effect of renal denervation may contribute to decreased neurohormone levels. Copyright © 2014 Sociedad Española de Cardiología. Published by Elsevier España, S.L.U. All rights reserved.

Turbulence-assisted shear exfoliation of graphene using household detergent and a kitchen blender

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Varrla, Eswaraiah; Paton, Keith R.; Backes, Claudia; Harvey, Andrew; Smith, Ronan J.; McCauley, Joe; Coleman, Jonathan N.

2014-09-01

To facilitate progression from the lab to commercial applications, it will be necessary to develop simple, scalable methods to produce high quality graphene. Here we demonstrate the production of large quantities of defect-free graphene using a kitchen blender and household detergent. We have characterised the scaling of both graphene concentration and production rate with the mixing parameters: mixing time, initial graphite concentration, rotor speed and liquid volume. We find the production rate to be invariant with mixing time and to increase strongly with mixing volume, results which are important for scale-up. Even in this simple system, concentrations of up to 1 mg ml-1 and graphene masses of >500 mg can be achieved after a few hours mixing. The maximum production rate was ~0.15 g h-1, much higher than for standard sonication-based exfoliation methods. We demonstrate that graphene production occurs because the mean turbulent shear rate in the blender exceeds the critical shear rate for exfoliation.To facilitate progression from the lab to commercial applications, it will be necessary to develop simple, scalable methods to produce high quality graphene. Here we demonstrate the production of large quantities of defect-free graphene using a kitchen blender and household detergent. We have characterised the scaling of both graphene concentration and production rate with the mixing parameters: mixing time, initial graphite concentration, rotor speed and liquid volume. We find the production rate to be invariant with mixing time and to increase strongly with mixing volume, results which are important for scale-up. Even in this simple system, concentrations of up to 1 mg ml-1 and graphene masses of >500 mg can be achieved after a few hours mixing. The maximum production rate was ~0.15 g h-1, much higher than for standard sonication-based exfoliation methods. We demonstrate that graphene production occurs because the mean turbulent shear rate in the blender exceeds

A Nanoporous Carbon/Exfoliated Graphite Composite For Supercapacitor Electrodes

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Rosi, Memoria; Ekaputra, Muhamad P.; Iskandar, Ferry; Abdullah, Mikrajuddin; Khairurrijal

2010-12-01

Nanoporous carbon was prepared from coconut shells using a simple heating method. The nanoporous carbon is subjected to different treatments: without activation, activation with polyethylene glycol (PEG), and activation with sodium hydroxide (NaOH)-PEG. The exfoliated graphite was synthesized from graphite powder oxidized with zinc acetate (ZnAc) and intercalated with polyvinyl alcohol (PVA) and NaOH. A composite was made by mixing the nanoporous carbon with NaOH-PEG activation, the exfoliated graphite and a binder of PVA solution, grinding the mixture, and annealing it using ultrasonic bath for 1 hour. All of as-synthesized materials were characterized by employing a scanning electron microscope (SEM), a MATLAB's image processing toolbox, and an x-ray diffractometer (XRD). It was confirmed that the composite is crystalline with (002) and (004) orientations. In addition, it was also found that the composite has a high surface area, a high distribution of pore sizes less than 40 nm, and a high porosity (67%). Noting that the pore sizes less than 20 nm are significant for ionic species storage and those in the range of 20 to 40 nm are very accessible for ionic clusters mobility across the pores, the composite is a promising material for the application as supercapacitor electrodes.

Gas storage cylinder formed from a composition containing thermally exfoliated graphite

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Prud'Homme, Robert K. (Inventor); Aksay, Ilhan A. (Inventor)

2012-01-01

A gas storage cylinder or gas storage cylinder liner, formed from a polymer composite, containing at least one polymer and a modified graphite oxide material, which is a thermally exfoliated graphite oxide with a surface area of from about 300 m(exp 2)/g to 2600 m(exp 2)2/g.

Ultrahigh-throughput exfoliation of graphite into pristine ‘single-layer’ graphene using microwaves and molecularly engineered ionic liquids

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Matsumoto, Michio; Saito, Yusuke; Park, Chiyoung; Fukushima, Takanori; Aida, Takuzo

2015-09-01

Graphene has shown much promise as an organic electronic material but, despite recent achievements in the production of few-layer graphene, the quantitative exfoliation of graphite into pristine single-layer graphene has remained one of the main challenges in developing practical devices. Recently, reduced graphene oxide has been recognized as a non-feasible alternative to graphene owing to variable defect types and levels, and attention is turning towards reliable methods for the high-throughput exfoliation of graphite. Here we report that microwave irradiation of graphite suspended in molecularly engineered oligomeric ionic liquids allows for ultrahigh-efficiency exfoliation (93% yield) with a high selectivity (95%) towards ‘single-layer’ graphene (that is, with thicknesses oligomeric ionic liquids up to ~100 mg ml-1, and form physical gels in which an anisotropic orientation of graphene sheets, once induced by a magnetic field, is maintained.

Paper Electrodes Coated with Partially-Exfoliated Graphite and Polypyrrole for High-Performance Flexible Supercapacitors

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Leping Huang

2018-01-01

Full Text Available Flexible paper electrodes for supercapacitors were prepared with partially-exfoliated graphite and polypyrrole as the active materials. Graphite was coated on paper with pencil drawing and then electrochemically exfoliated using the cyclic voltammetry (CV technique to obtain the exfoliated graphite (EG-coated paper (EG-paper. Polypyrrole (PPy doped with β-naphthalene sulfonate anions was deposited on EG-paper through in-situ polymerization, leading to the formation of PPy-EG-paper. The as-prepared PPy-EG-paper showed a high electrical conductivity of 10.0 S·cm−1 and could be directly used as supercapacitor electrodes. The PPy-EG-paper electrodes gave a remarkably larger specific capacitance of 2148 F∙g−1 at a current density of 0.8 mA∙cm−2, compared to PPy-graphite-paper (848 F∙g−1. The capacitance value of PPy-EG-paper could be preserved by 80.4% after 1000 charge/discharge cycles. In addition, the PPy-EG-paper electrodes demonstrated a good rate capability and a high energy density of 110.3 Wh∙kg−1 at a power density of 121.9 W∙kg−1. This work will pave the way for the discovery of efficient paper-based electrode materials.

γδ T cells are required for pulmonary IL-17A expression after ozone exposure in mice: role of TNFα.

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Joel A Mathews

Full Text Available Ozone is an air pollutant that causes pulmonary symptoms. In mice, ozone exposure causes pulmonary injury and increases bronchoalveolar lavage macrophages and neutrophils. We have shown that IL-17A is important in the recruitment of neutrophils after subacute ozone exposure (0.3 ppm for 24-72 h. We hypothesized that γδ T cells are the main producers of IL-17A after subacute ozone. To explore this hypothesis we exposed wildtype mice and mice deficient in γδ T cells (TCRδ-/- to ozone or room air. Ozone-induced increases in BAL macrophages and neutrophils were attenuated in TCRδ-/- mice. Ozone increased the number of γδ T cells in the lungs and increased pulmonary Il17a mRNA expression and the number of IL-17A+ CD45+ cells in the lungs and these effects were abolished in TCRδ-/- mice. Ozone-induced increases in factors downstream of IL-17A signaling, including G-CSF, IL-6, IP-10 and KC were also decreased in TCRδ-/- versus wildtype mice. Neutralization of IL-17A during ozone exposure in wildtype mice mimicked the effects of γδ T cell deficiency. TNFR2 deficiency and etanercept, a TNFα antagonist, also reduced ozone-induced increases in Il17a mRNA, IL-17A+ CD45+ cells and BAL G-CSF as well as BAL neutrophils. TNFR2 deficient mice also had decreased ozone-induced increases in Ccl20, a chemoattractant for IL-17A+ γδ T cells. Il17a mRNA and IL-17A+ γδ T cells were also lower in obese Cpefat versus lean WT mice exposed to subacute ozone, consistent with the reduced neutrophil recruitment observed in the obese mice. Taken together, our data indicate that pulmonary inflammation induced by subacute ozone requires γδ T cells and TNFα-dependent recruitment of IL-17A+ γδ T cells to the lung.

Lack of bcr and abr promotes hypoxia-induced pulmonary hypertension in mice.

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Min Yu

Full Text Available Bcr and Abr are GTPase activating proteins that specifically downregulate activity of the small GTPase Rac in restricted cell types in vivo. Rac1 is expressed in smooth muscle cells, a critical cell type involved in the pathogenesis of pulmonary hypertension. The molecular mechanisms that underlie hypoxia-associated pulmonary hypertension are not well-defined.Bcr and abr null mutant mice were compared to wild type controls for the development of pulmonary hypertension after exposure to hypoxia. Also, pulmonary arterial smooth muscle cells from those mice were cultured in hypoxia and examined for proliferation, p38 activation and IL-6 production. Mice lacking Bcr or Abr exposed to hypoxia developed increased right ventricular pressure, hypertrophy and pulmonary vascular remodeling. Perivascular leukocyte infiltration in the lungs was increased, and under hypoxia bcr-/- and abr-/- macrophages generated more reactive oxygen species. Consistent with a contribution of inflammation and oxidative stress in pulmonary hypertension-associated vascular damage, Bcr and Abr-deficient animals showed elevated endothelial leakage after hypoxia exposure. Hypoxia-treated pulmonary arterial smooth muscle cells from Bcr- or Abr-deficient mice also proliferated faster than those of wild type mice. Moreover, activated Rac1, phosphorylated p38 and interleukin 6 were increased in these cells in the absence of Bcr or Abr. Inhibition of Rac1 activation with Z62954982, a novel Rac inhibitor, decreased proliferation, p38 phosphorylation and IL-6 levels in pulmonary arterial smooth muscle cells exposed to hypoxia.Bcr and Abr play a critical role in down-regulating hypoxia-induced pulmonary hypertension by deactivating Rac1 and, through this, reducing both oxidative stress generated by leukocytes as well as p38 phosphorylation, IL-6 production and proliferation of pulmonary arterial smooth muscle cells.

Angiostatic factors in the pulmonary endarterectomy material from chronic thromboembolic pulmonary hypertension patients cause endothelial dysfunction.

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Diana Zabini

Full Text Available Chronic thromboembolic pulmonary hypertension (CTEPH is a rare disease with persistent thrombotic occlusion or stenosis of the large pulmonary arteries resulting in pulmonary hypertension. Surgical removal of the neointimal layer of these vessels together with the non-resolved thrombus consisting of organized collagen-rich fibrotic areas with partly recanalized regions is the treatment of choice (pulmonary endarterectomy, PEA. The present study investigates endothelial cells isolated from such material as well as factors present in the surgical PEA material, which may contribute to impairment of recanalization and thrombus non-resolution. We observed muscularized vessels and non-muscularized vessels in the PEA material. The isolated endothelial cells from the PEA material showed significantly different calcium homeostasis as compared to pulmonary artery endothelial cells (hPAECs from normal controls. In the supernatant (ELISA as well as on the tissue level (histochemical staining of the PEA material, platelet factor 4 (PF4, collagen type I and interferon-gamma-inducible 10 kD protein (IP-10 were detected. CXCR3, the receptor for PF4 and IP-10, was particularly elevated in the distal parts of the PEA material as compared to human control lung (RT-PCR. PF4, collagen type I and IP-10 caused significant changes in calcium homeostasis and affected the cell proliferation, migration and vessel formation in hPAECs. The presence of angiostatic factors like PF4, collagen type I and IP-10, as recovered from the surgical PEA material from CTEPH patients, may lead to changes in calcium homeostasis and endothelial dysfunction.

Performance of Liquid Phase Exfoliated Graphene As Electrochemical Double Layer Capacitors Electrodes

Science.gov (United States)

Huffstutler, Jacob; Wasala, Milinda; Richie, Julianna; Winchester, Andrew; Ghosh, Sujoy; Kar, Swastik; Talapatra, Saikat

2014-03-01

We will present the results of our investigations of electrochemical double layer capacitors (EDLCs) or supercapacitors (SC) fabricated using liquid-phase exfoliated graphene. Several electrolytes, such as aqueous potassium hydroxide KOH (6M), ionic 1-Butyl-3-methylimidazolium hexafluorophosphate [BMIM][PF6], and ionic 1-butyl-1-methylpyrrolidinium tris(pentafluoroethyl)trifluorophosphate[BMP][FAP] were used. These EDLC's show good performance compared to other carbon nanomaterials based EDLC's devices. We found that the liquid phase exfoliated graphene based devices possess specific capacitance values as high as 262 F/g, when used with ionic liquid electrolyte[BMP][FAP], with power densities (~ 454 W/kg) and energy densities (~ 0.38Wh/kg). Further, these devices indicated rapid charge transfer response even without the use of any binders or specially prepared current collectors. A detailed electrochemical impedance spectroscopy analysis in order to understand the phenomenon of charge storage in these materials will be presented.

Single-Nanoflake Photo-Electrochemistry Reveals Champion and Spectator Flakes in Exfoliated MoSe2 Films

Energy Technology Data Exchange (ETDEWEB)

Link, Elisa M [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Nanayakkara, Sanjini U [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Todt, Michael A. [Colorado State University; Isenberg, Allan E. [Colorado State University; Sambur, Justin B. [Colorado State University

2018-03-06

Semiconducting transition-metal dichalcogenide (TMD) nanoflake thin films are promising large-area electrodes for photo-electrochemical solar energy conversion applications. However, their energy conversion efficiencies are typically much lower than those of bulk electrodes. It is unclear to what extent this efficiency gap stems from differences among nanoflakes (e.g., area, thickness, and surface structural features). It is also unclear whether individual exfoliated nanoflakes can achieve energy conversion efficiencies similar to those of bulk crystals. Here, we use a single-nanoflake photo-electrochemical approach to show that there are both highly active and completely inactive nanoflakes within a film. For the exfoliated MoSe2 samples studied herein, 7% of nanoflakes are highly active champions, whose photocurrent efficiency exceeds that of the bulk crystal. However, 66% of nanoflakes are inactive spectators, which are mostly responsible for the overall lower photocurrent efficiency compared to the bulk crystal. The photocurrent collection efficiency increases with nanoflake area and decreases more at perimeter edges than at interior step edges. These observations, which are hidden in ensemble-level measurements, reveal the underlying performance issues of exfoliated TMD electrodes for photo-electrochemical energy conversion applications.

[Pulmonary sarcomatoid carcinoma].

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Antoine, Martine; Vieira, Thibault; Fallet, Vincent; Hamard, Cécile; Duruisseaux, Michael; Cadranel, Jacques; Wislez, Marie

2016-01-01

Pulmonary sarcomatoid carcinomas are a rare group of tumors accounting for about one percent of non-small cell lung carcinoma (NSCLC). In 2015, the World Health Organization classification united under this name all the carcinomas with sarcomatous-like component with spindle cell or giant cell appearance, or associated with a sarcomatous component sometimes heterologous. There are five subtypes: pleomorphic carcinoma, spindle cell carcinoma, giant cell carcinoma, carcinosarcoma and pulmonary blastoma. Clinical characteristics are not specific from the other subtypes of NSCLC. Epithelial to mesenchymal transition pathway may play a key role. Patients, usually tobacco smokers, are frequently symptomatic. Tumors are voluminous more often peripherical than central, with strong fixation on FDG TEP CT. Distant metastases are frequent with atypical visceral locations. These tumors have poorer prognosis than the other NSCLC subtypes because of great aggressivity, and frequent chemoresistance. Here we present pathological description and a review of literature with molecular features in order to better describe these tumors and perhaps introduce new therapeutics. Copyright © 2016. Published by Elsevier Masson SAS.

Environmental Synthesis of Few Layers Graphene Sheets Using Ultrasonic Exfoliation with Enhanced Electrical and Thermal Properties.

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Monir Noroozi

Full Text Available In this paper, we report how few layers graphene that can be produced in large quantity with low defect ratio from exfoliation of graphite by using a high intensity probe sonication in water containing liquid hand soap and PVP. It was founded that the graphene powder obtained by this simple exfoliation method after the heat treatment had an excellent exfoliation into a single or layered graphene sheets. The UV-visible spectroscopy, FESEM, TEM, X-ray powder diffraction and Raman spectroscopy was used to analyse the graphene product. The thermal diffusivity of the samples was analysed using a highly accurate thermal-wave cavity photothermal technique. The data obtained showed excellent enhancement in the thermal diffusivity of the graphene dispersion. This well-dispersed graphene was then used to fabricate an electrically conductive polymer-graphene film composite. The results demonstrated that this low cost and environmental friendly technique allowed to the production of high quality layered graphene sheets, improved the thermal and electrical properties. This may find use in the wide range of applications based on graphene.

Fabrication of fluorographene nanosheets with high yield and good quality based on supercritical fluid-phase exfoliation

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Chen, Qi; Ji, Yan; Zhang, Danying; Shi, Jia [Nanjing University of Science and Technology, Key Laboratory of Soft Chemistry and Functional Materials, College of Chemical Engineering (China); Xiao, Yinghong, E-mail: yhxiao@njnu.edu.cn [Nanjing Normal University, Jiangsu Collaborative Innovation Center of Biomedical Functional Materials, College of Chemistry and Materials Science (China); Che, Jianfei, E-mail: xiaoche@mail.njust.edu.cn [Nanjing University of Science and Technology, Key Laboratory of Soft Chemistry and Functional Materials, College of Chemical Engineering (China)

2016-07-15

This article presents a novel and simple method of supercritical fluid-phase exfoliation to fabricate fluorographene (FG) nanosheets with high yield and good quality. After soaking with supercritical CO{sub 2} and glycol at 10 MPa and 50 °C for 24 h, fluoride graphite powder was exfoliated by the intercalated CO{sub 2} and glycol molecules during an abrupt depressurization step. Here, supercritical CO{sub 2} acted as a penetrant and glycol acted as a “molecular wedge” to exfoliate fluoride graphite very well. The properties of FG nanosheets were detected by TEM, AFM, UV spectra, FTIR, XPS, Raman spectra, and XRD, which show the possibility of producing thickness-controlled FG nanosheets by varying numbers of supercritical CO{sub 2} process and the high yield of pure FG nanosheets of 32 wt%, four times higher than that of the sample treated only by the traditional method of sonication. Its simplicity, high productivity, low cost, and short processing time make this technique suitable for large-scale manufacturing of FG nanosheets.

Long-term change in pulmonary function after definitive radiotherapy for non-small cell lung cancer

DEFF Research Database (Denmark)

Schytte, T.; Bentzen, S. M.; Brink, C.

2015-01-01

Purpose/Objective: Radiotherapy (RT) for non-small cell lung cancer (NSCLC) may cause late toxicities, such as heart toxicity, changes in pulmonary function (PF) and lung fibrosis, but late toxicity data are scarce in the literature for this category of patients. The objective of this study...... with 3063 pairs of pulmonary function test (PFTs) were screened for eligibility for inclusion in the analysis of late changes in PF. To be eligible, patients had at least 3 PFTs after baseline. In this study, baseline was defined as 12 months after RT commencement to overcome a possible effect of tumor...... finding was that high V60 was associated with less decline in FVC, but FVC may be a less reliable parameter for pulmonary damage. (Figure Presented) Conclusions: Patients experience a decline in FEV1 after the 12-month value following definitive RT for NSCLC. In a multivariable analysis, deterioration...

Diffuse idiopathic pulmonary neuroendocrine cell hyperplasia: Report of two cases.

Science.gov (United States)

García-Fontán, Eva; Blanco Ramos, Montserrat; García, Jose Soro; Carrasco, Rommel; Cañizares, Miguel Ángel; González Piñeiro, Ana

2018-05-19

Diffuse idiopathic pulmonary neuroendocrine cell hyperplasia (DIPNECH) is a rare disorder characterized by a proliferation of neuroendocrine cells within the lung. It is classically described as a disease with persistent cough, dyspnea and wheezing in non-smoker middle aged females. CT of the chest reveals diffuse air trapping with mosaic pattern. We present two cases of DIPNECH that were sent to our department to perform a lung biopsy with the diagnostic suspicion of diffuse interstitial disease. Both cases were women with a history of chronic cough and moderate effort dyspnea. The aim of this paper is that physicians take into account this diagnostic entity before treating as an asthmatic a patient with these characteristics, not forgetting that they are prenoplastic lesions. Copyright © 2018 Elsevier España, S.L.U. All rights reserved.

Graphene Oxide Quantum Dots Exfoliated From Carbon Fibers by Microwave Irradiation: Two Photoluminescence Centers and Self-Assembly Behavior.

Science.gov (United States)

Yuan, Jian-Min; Zhao, Rui; Wu, Zhen-Jun; Li, Wei; Yang, Xin-Guo

2018-04-17

Graphene oxide quantum dots (GOQDs) attract great attention for their unique properties and promising application potential. The difficulty in the formation of a confined structure, and the numerous and diverse oxygen-containing functional groups results in a low emission yield to GOQDs. Here, GOQDs with a size of about 5 nm, exfoliated from carbon fibers by microwave irradiation, are detected and analyzed. The exfoliated GOQDs are deeply oxidized and induce large numbers of epoxy groups and ether bonds, but only a small amount of carbonyl groups and hydroxyl groups. The subdomains of sp 2 clusters, involving epoxy groups and ether bonds, are responsible for the two strong photoluminescence emissions of GOQDs under different excitation wavelengths. Moreover, GOQDs tend to self-assemble at the edges of their planes to form self-assembly films (SAFs) with the evaporation of water. SAFs can further assemble into different 3D patterns with unique microstructures such as sponge bulk, sponge ball, microsheet, sisal, and schistose coral, which are what applications such as supercapacitors, cells, catalysts, and electrochemical sensors need. This method for preparation of GOQDs is easy, quick, and environmentally friendly, and this work may open up new research interests about GOQDs. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Luminescent monolayer MoS{sub 2} quantum dots produced by multi-exfoliation based on lithium intercalation

Energy Technology Data Exchange (ETDEWEB)

Qiao, Wen [Collaborative Innovation Center of Advanced Microstructures, National Laboratory of Solid State Microstructures and Jiangsu Provincial Laboratory for NanoTechnology, Nanjing University, Nanjing 210093 (China); Yan, Shiming [Collaborative Innovation Center of Advanced Microstructures, National Laboratory of Solid State Microstructures and Jiangsu Provincial Laboratory for NanoTechnology, Nanjing University, Nanjing 210093 (China); College of Science, Henan University of Technology, Zhengzhou 450001 (China); Song, Xueyin; Zhang, Xing; He, Xueming [Collaborative Innovation Center of Advanced Microstructures, National Laboratory of Solid State Microstructures and Jiangsu Provincial Laboratory for NanoTechnology, Nanjing University, Nanjing 210093 (China); Zhong, Wei, E-mail: wzhong@nju.edu.cn [Collaborative Innovation Center of Advanced Microstructures, National Laboratory of Solid State Microstructures and Jiangsu Provincial Laboratory for NanoTechnology, Nanjing University, Nanjing 210093 (China); Du, Youwei [Collaborative Innovation Center of Advanced Microstructures, National Laboratory of Solid State Microstructures and Jiangsu Provincial Laboratory for NanoTechnology, Nanjing University, Nanjing 210093 (China)

2015-12-30

Graphical abstract: - Highlights: • A new preparation, multi-exfoliation method based on lithium (Li) intercalation, has been demonstrated for preparing monolayer molybdenum disulfide (MoS{sub 2}) quantum dots (QDs). • The advantage of this approach is that it is capable of producing monolayer MoS{sub 2} QDs in a large number, regardless of whether the raw material is bulk or nanoparticles. • The PL intensity excited at 300 nm can be enhanced by five times after ultrasonicated heating treatment. - Abstract: An effective multi-exfoliation method based on lithium (Li) intercalation has been demonstrated for preparing monolayer molybdenum disulfide (MoS{sub 2}) quantum dots (QDs). The cutting mechanism of MoS{sub 2} QDs may involve the complete breakup around the defects and edges during the reaction of Li{sub x}MoS{sub 2} with water and its following ultrasonication process. The multiply exfoliation make the MoS{sub 2} fragile and easier to break up. After the third exfoliation, a large number of monolayer MoS{sub 2} QDs is formed. The as-prepared MoS{sub 2} QDs show photoluminescence (PL) inactive due to the existence of 1T phase. After heating treatment, the PL intensity excited at 300 nm is enhanced by five times. The MoS{sub 2} QDs solution has an excitation-dependent luminescence emission which shifts to longer wavelengths when the excitation wavelength changes from 280 nm to 370 nm. The optical properties are explored based on the quantum confinement and edge effect.

The zinc transporter ZIP12 regulates the pulmonary vascular response to chronic hypoxia.

Science.gov (United States)

Zhao, Lan; Oliver, Eduardo; Maratou, Klio; Atanur, Santosh S; Dubois, Olivier D; Cotroneo, Emanuele; Chen, Chien-Nien; Wang, Lei; Arce, Cristina; Chabosseau, Pauline L; Ponsa-Cobas, Joan; Frid, Maria G; Moyon, Benjamin; Webster, Zoe; Aldashev, Almaz; Ferrer, Jorge; Rutter, Guy A; Stenmark, Kurt R; Aitman, Timothy J; Wilkins, Martin R

2015-08-20

The typical response of the adult mammalian pulmonary circulation to a low oxygen environment is vasoconstriction and structural remodelling of pulmonary arterioles, leading to chronic elevation of pulmonary artery pressure (pulmonary hypertension) and right ventricular hypertrophy. Some mammals, however, exhibit genetic resistance to hypoxia-induced pulmonary hypertension. We used a congenic breeding program and comparative genomics to exploit this variation in the rat and identified the gene Slc39a12 as a major regulator of hypoxia-induced pulmonary vascular remodelling. Slc39a12 encodes the zinc transporter ZIP12. Here we report that ZIP12 expression is increased in many cell types, including endothelial, smooth muscle and interstitial cells, in the remodelled pulmonary arterioles of rats, cows and humans susceptible to hypoxia-induced pulmonary hypertension. We show that ZIP12 expression in pulmonary vascular smooth muscle cells is hypoxia dependent and that targeted inhibition of ZIP12 inhibits the rise in intracellular labile zinc in hypoxia-exposed pulmonary vascular smooth muscle cells and their proliferation in culture. We demonstrate that genetic disruption of ZIP12 expression attenuates the development of pulmonary hypertension in rats housed in a hypoxic atmosphere. This new and unexpected insight into the fundamental role of a zinc transporter in mammalian pulmonary vascular homeostasis suggests a new drug target for the pharmacological management of pulmonary hypertension.

Pulmonary infection in AIDS

International Nuclear Information System (INIS)

Kim, Seog Joon; Im, Jung Gi; Seong, Chang Kyu; Yeon, Kyung Mo; Han, Man Chung; Song, Jae Woo

1998-01-01

To analyze the clinical and radiological manifestations of pulmonary infection in patients with AIDS. We reviewed the medical records and analyzed retrospectively analysed the chest radiographs(n=3D24) and CT scans(n=3D11) of 26 patients with AIDS who had been followed up at our institute from 1987 to June 1998. Pulmonary infections were confirmed by sputum smear and culture(n=3D18), pleural examination(n=3D3), bronchoalveolar lavage(n=3D3), autopsy(n=3D4), transbronchial lung biopsy(n=3D1) or clinical history(n=3D9). The study group included 23 men and three women aged 25-54(average 35.2) years. We correlated the radiologic findings with CD4 lymphocyte counts. Pulmonary infections included tuberculosis(n=3D22), pneumocystis carinii pneumonia(n=3D9), cytomegalovirus(n=3D3), and unidentified bacterial pneumonia(n=3D2). Radiologically pulmonary tuberculosis was classified as primary tuberculosis(n=3D11;mean CD4 counts:41.3 cells/mm 3 ) and post-primary tuberculosis(n=3D11;mean CD4 counts:251.3cells/mm 3 ). CT findings of tuberculosis included lymphadenitis(n=3D6), bronchogenic spread(n=3D5), large consolidation(n=3D4), esophago-mediastinal fistula(n=3D2), and cavity(n=3D1). Tuberculosis in AIDS responded rapidly to anti-TB medication with complete or marked resolution of lesions within three months. Radiologic findings of Pneumocystis carinii pneumonia included diffuse ground glass opacities, cysts, and reticular opacities. Tuberculosis was the most common infection in patients with AIDS in Korea, and this is attributed to the high prevalence of tuberculosis. Radiological findings varied with CD4+cell count, showing those of primary tuberculosis as a patient's CD4+ cell count decreased. Pulmonary tuberculosis in AIDS responded rapidly to anti-Tb medication. =20

Protective roles of pulmonary rehabilitation mixture in experimental pulmonary fibrosis in vitro and in vivo

Energy Technology Data Exchange (ETDEWEB)

Zhang, L.; Ji, Y.X.; Jiang, W.L.; Lv, C.J. [School of Pharmaceutical Sciences, Binzhou Medical University, Yantai (China)

2015-05-08

Abnormal high mobility group protein B1 (HMGB1) activation is involved in the pathogenesis of pulmonary fibrosis. Pulmonary rehabilitation mixture (PRM), which combines extracts from eight traditional Chinese medicines, has very good lung protection in clinical use. However, it is not known if PRM has anti-fibrotic activity. In this study, we investigated the effects of PRM on transforming growth factor-β1 (TGF-β1)-mediated and bleomycin (BLM)-induced pulmonary fibrosis in vitro and in vivo. The effects of PRM on TGF-β1-mediated epithelial-mesenchymal transition (EMT) in A549 cells, on the proliferation of human lung fibroblasts (HLF-1) in vitro, and on BLM-induced pulmonary fibrosis in vivo were investigated. PRM treatment resulted in a reduction of EMT in A549 cells that was associated with attenuating an increase of vimentin and a decrease of E-cadherin. PRM inhibited the proliferation of HLF-1 at an IC{sub 50} of 0.51 µg/mL. PRM ameliorated BLM-induced pulmonary fibrosis in rats, with reduction of histopathological scores and collagen deposition, and a decrease in α-smooth muscle actin (α-SMA) and HMGB1 expression. An increase in receptor for advanced glycation end-product (RAGE) expression was found in BLM-instilled lungs. PRM significantly decreased EMT and prevented pulmonary fibrosis through decreasing HMGB1 and regulating RAGE in vitro and in vivo. PRM inhibited TGF-β1-induced EMT via decreased HMGB1 and vimentin and increased RAGE and E-cadherin levels. In summary, PRM prevented experimental pulmonary fibrosis by modulating the HMGB1/RAGE pathway.

Protective roles of pulmonary rehabilitation mixture in experimental pulmonary fibrosis in vitro and in vivo

International Nuclear Information System (INIS)

Zhang, L.; Ji, Y.X.; Jiang, W.L.; Lv, C.J.

2015-01-01

Abnormal high mobility group protein B1 (HMGB1) activation is involved in the pathogenesis of pulmonary fibrosis. Pulmonary rehabilitation mixture (PRM), which combines extracts from eight traditional Chinese medicines, has very good lung protection in clinical use. However, it is not known if PRM has anti-fibrotic activity. In this study, we investigated the effects of PRM on transforming growth factor-β1 (TGF-β1)-mediated and bleomycin (BLM)-induced pulmonary fibrosis in vitro and in vivo. The effects of PRM on TGF-β1-mediated epithelial-mesenchymal transition (EMT) in A549 cells, on the proliferation of human lung fibroblasts (HLF-1) in vitro, and on BLM-induced pulmonary fibrosis in vivo were investigated. PRM treatment resulted in a reduction of EMT in A549 cells that was associated with attenuating an increase of vimentin and a decrease of E-cadherin. PRM inhibited the proliferation of HLF-1 at an IC 50 of 0.51 µg/mL. PRM ameliorated BLM-induced pulmonary fibrosis in rats, with reduction of histopathological scores and collagen deposition, and a decrease in α-smooth muscle actin (α-SMA) and HMGB1 expression. An increase in receptor for advanced glycation end-product (RAGE) expression was found in BLM-instilled lungs. PRM significantly decreased EMT and prevented pulmonary fibrosis through decreasing HMGB1 and regulating RAGE in vitro and in vivo. PRM inhibited TGF-β1-induced EMT via decreased HMGB1 and vimentin and increased RAGE and E-cadherin levels. In summary, PRM prevented experimental pulmonary fibrosis by modulating the HMGB1/RAGE pathway

Exfoliation on stainless steel and inconel produced by 0.8-4 MeV helium ion bombardment

International Nuclear Information System (INIS)

Paszti, F.; Mezey, G.; Pogany, L.; Fried, M.; Manuaba, A.; Kotai, E.; Lohner, T.; Pocs, L.

1982-11-01

Trying to outline the energy dependence of surface deformations such as exfoliation and flaking on candidate CTR first-wall materials, stainless steel and two types of inconels were bombarded by 0.8, 1 and 4 MeV helium ions. All the bombarded spots could be characterized by by large exfoliations covering almost the total implanted area. No spontaneous rupture was observed except on one type of inconel where flaking took place right after reaching the critical dose. After mechanical opening of the formations, similar inner morphology was found as in our previous studies on gold. (author)

Repetitive intradermal bleomycin injections evoke T-helper cell 2 cytokine-driven pulmonary fibrosis.

Science.gov (United States)

Singh, Brijendra; Kasam, Rajesh K; Sontake, Vishwaraj; Wynn, Thomas A; Madala, Satish K

2017-11-01

IL-4 and IL-13 are major T-helper cell (Th) 2 cytokines implicated in the pathogenesis of several lung diseases, including pulmonary fibrosis. In this study, using a novel repetitive intradermal bleomycin model in which mice develop extensive lung fibrosis and a progressive decline in lung function compared with saline-treated control mice, we investigated profibrotic functions of Th2 cytokines. To determine the role of IL-13 signaling in the pathogenesis of bleomycin-induced pulmonary fibrosis, wild-type, IL-13, and IL-4Rα-deficient mice were treated with bleomycin, and lungs were assessed for changes in lung function and pulmonary fibrosis. Histological staining and lung function measurements demonstrated that collagen deposition and lung function decline were attenuated in mice deficient in either IL-13 or IL-4Rα-driven signaling compared with wild-type mice treated with bleomycin. Furthermore, our results demonstrated that IL-13 and IL-4Rα-driven signaling are involved in excessive migration of macrophages and fibroblasts. Notably, our findings demonstrated that IL-13-driven migration involves increased phospho-focal adhesion kinase signaling and F-actin polymerization. Importantly, in vivo findings demonstrated that IL-13 augments matrix metalloproteinase (MMP)-2 and MMP9 activity that has also been shown to increase migration and invasiveness of fibroblasts in the lungs during bleomycin-induced pulmonary fibrosis. Together, our findings demonstrate a pathogenic role for Th2-cytokine signaling that includes excessive migration and protease activity involved in severe fibrotic lung disease.

Upregulated copper transporters in hypoxia-induced pulmonary hypertension.

Directory of Open Access Journals (Sweden)

Adriana M Zimnicka

Full Text Available Pulmonary vascular remodeling and increased arterial wall stiffness are two major causes for the elevated pulmonary vascular resistance and pulmonary arterial pressure in patients and animals with pulmonary hypertension. Cellular copper (Cu plays an important role in angiogenesis and extracellular matrix remodeling; increased Cu in vascular smooth muscle cells has been demonstrated to be associated with atherosclerosis and hypertension in animal experiments. In this study, we show that the Cu-uptake transporter 1, CTR1, and the Cu-efflux pump, ATP7A, were both upregulated in the lung tissues and pulmonary arteries of mice with hypoxia-induced pulmonary hypertension. Hypoxia also significantly increased expression and activity of lysyl oxidase (LOX, a Cu-dependent enzyme that causes crosslinks of collagen and elastin in the extracellular matrix. In vitro experiments show that exposure to hypoxia or treatment with cobalt (CoCl2 also increased protein expression of CTR1, ATP7A, and LOX in pulmonary arterial smooth muscle cells (PASMC. In PASMC exposed to hypoxia or treated with CoCl2, we also confirmed that the Cu transport is increased using 64Cu uptake assays. Furthermore, hypoxia increased both cell migration and proliferation in a Cu-dependent manner. Downregulation of hypoxia-inducible factor 1α (HIF-1α with siRNA significantly attenuated hypoxia-mediated upregulation of CTR1 mRNA. In summary, the data from this study indicate that increased Cu transportation due to upregulated CTR1 and ATP7A in pulmonary arteries and PASMC contributes to the development of hypoxia-induced pulmonary hypertension. The increased Cu uptake and elevated ATP7A also facilitate the increase in LOX activity and thus the increase in crosslink of extracellular matrix, and eventually leading to the increase in pulmonary arterial stiffness.

Allogeneic stem cells derived from human exfoliated deciduous teeth (SHED for the management of periapical lesions in permanent teeth: Two case reports of a novel biologic alternative treatment

Directory of Open Access Journals (Sweden)

Madu Ghana Shyam Prasad

2017-06-01

Full Text Available Stem cells are the pluripotent cells that have the capacity to differentiate into other specialized cells. Recently, many experiments have been conducted to study the potentiality of stem cells in the tissue regeneration. We report two cases treated utilizing stem cells from human exfoliated deciduous teeth (SHED in the management of periapical lesions in permanent teeth. Two normal human deciduous teeth from children, 7‒8 years of age, were collected to isolate stem cells. Two patients, one with periapical pathology alone and the other with periapical lesion along with an open apex in young permanent teeth, were selected for the study. After initial debridement of the root canals, homing of SHED was carried out and the access cavity was sealed using glass-ionomer cement. Clinical examination after 7 days, 30 days, 90 days, 180 days and 365 days revealed no symptoms. Closure of open apex and periapical tissue healing were observed radiographically at one-month review and maintained until 365-day review. Positive response to electric pulp testing was recorded for the treated teeth from the 3- to 12-month follow-ups. The treated cases demonstrated complete resolution of periapical radiolucency in a span of 30 days, which was faster than the conventional methods. SHED could be considred effective in treating the periapical lesions and open apex in permanent teeth.

RELM-β promotes human pulmonary artery smooth muscle cell proliferation via FAK-stimulated surviving

International Nuclear Information System (INIS)

Lin, Chunlong; Li, Xiaohui; Luo, Qiong; Yang, Hui; Li, Lun; Zhou, Qiong; Li, Yue; Tang, Hao; Wu, Lifu

2017-01-01

Resistin-like molecule-β (RELM-β), focal adhesion kinase (FAK), and survivin may be involved in the proliferation of cultured human pulmonary artery smooth muscle cells (HPAMSCs), which is involved in pulmonary hypertension. HPAMSCs were treated with human recombinant RELM-β (rhRELM-β). siRNAs against FAK and survivin were transfected into cultured HPASMCs. Expression of FAK and survivin were examined by RT-PCR and western blot. Immunofluorescence was used to localize FAK. Flow cytometry was used to examine cell cycle distribution and cell death. Compared to the control group, all rhRELM-β-treated groups demonstrated significant increases in the expression of FAK and survivin (P<0.05). rhRELM-β significantly increased the proportion of HPASMCs in the S phase and decreased the proportion in G0/G1. FAK siRNA down-regulated survivin expression while survivin siRNA did not affect FAK expression. FAK siRNA effectively inhibited FAK and survivin expression in RELM-β-treated HPASMCs and partially suppressed cell proliferation. RELM-β promoted HPASMC proliferation and upregulated FAK and survivin expression. In conclusion, results suggested that FAK is upstream of survivin in the signaling pathway mediating cell proliferation. FAK seems to be important in RELM-β-induced HPASMC proliferation, partially by upregulating survivin expression. - Highlights: • rhRELM-β increased the expression of FAK and survivin. • rhRELM-β increased the proportion of HPASMCs in the S phase. • FAK is upstream of survivin in the signaling pathway mediating cell proliferation. • FAK is important in RELM-β-induced HPASMC proliferation, partly via survivin.

RELM-β promotes human pulmonary artery smooth muscle cell proliferation via FAK-stimulated surviving

Energy Technology Data Exchange (ETDEWEB)

Lin, Chunlong, E-mail: lclmd@sina.com; Li, Xiaohui; Luo, Qiong; Yang, Hui; Li, Lun; Zhou, Qiong; Li, Yue; Tang, Hao; Wu, Lifu

2017-02-01

Resistin-like molecule-β (RELM-β), focal adhesion kinase (FAK), and survivin may be involved in the proliferation of cultured human pulmonary artery smooth muscle cells (HPAMSCs), which is involved in pulmonary hypertension. HPAMSCs were treated with human recombinant RELM-β (rhRELM-β). siRNAs against FAK and survivin were transfected into cultured HPASMCs. Expression of FAK and survivin were examined by RT-PCR and western blot. Immunofluorescence was used to localize FAK. Flow cytometry was used to examine cell cycle distribution and cell death. Compared to the control group, all rhRELM-β-treated groups demonstrated significant increases in the expression of FAK and survivin (P<0.05). rhRELM-β significantly increased the proportion of HPASMCs in the S phase and decreased the proportion in G0/G1. FAK siRNA down-regulated survivin expression while survivin siRNA did not affect FAK expression. FAK siRNA effectively inhibited FAK and survivin expression in RELM-β-treated HPASMCs and partially suppressed cell proliferation. RELM-β promoted HPASMC proliferation and upregulated FAK and survivin expression. In conclusion, results suggested that FAK is upstream of survivin in the signaling pathway mediating cell proliferation. FAK seems to be important in RELM-β-induced HPASMC proliferation, partially by upregulating survivin expression. - Highlights: • rhRELM-β increased the expression of FAK and survivin. • rhRELM-β increased the proportion of HPASMCs in the S phase. • FAK is upstream of survivin in the signaling pathway mediating cell proliferation. • FAK is important in RELM-β-induced HPASMC proliferation, partly via survivin.

Radionuclide angiocardiography in pulmonary hypertension: hemodynamic data relationship

Energy Technology Data Exchange (ETDEWEB)

Lopes, A A.B.; Meneguetti, J C; Soares, Junior, J; Ratti, A N; Ebaid, M; Camargo, E E

1988-05-01

Eighteen patients with primary or secondary pulmonary hypertension were studied. Radionuclide angiocardiographic data were obtained by in vivo red blood cell labeling with technetium-99m pertechnetate. A pulmonary time-activity curve was plotted using the firstpass technique. The first derivative of the upstroke of the time-activity curve was normalized to the maximum count rate of the pulmonary time-activity curve (Dmax), and compared to mean pulmonary arterial pressure (PAP), Pulmonary resistence (Rp) and the ratio Rp/Rs. (M.A.C.).

Radionuclide angiocardiography in pulmonary hypertension: hemodynamic data relationship

International Nuclear Information System (INIS)

Lopes, A.A.B.; Meneguetti, J.C.; Soares Junior, J.; Ratti, A.N.; Ebaid, M.; Camargo, E.E.

1988-01-01

Eighteen patients with primary or secondary pulmonary hypertension were studied. Radionuclide angiocardiographic data were obtained by in vivo red blood cell labeling with technetium-99m pertechnetate. A pulmonary time-activity curve was plotted using the firstpass technique. The first derivative of the upstroke of the time-activity curve was normalized to the maximum count rate of the pulmonary time-activity curve (Dmax), and compared to mean pulmonary arterial pressure (PAP), Pulmonary resistence (Rp) and the ratio Rp/Rs. (M.A.C.) [pt

Facile and Green Production of Impurity-Free Aqueous Solutions of WS2 Nanosheets by Direct Exfoliation in Water.

Science.gov (United States)

Pan, Long; Liu, Yi-Tao; Xie, Xu-Ming; Ye, Xiong-Ying

2016-12-01

To obtain 2D materials with large quantity, low cost, and little pollution, liquid-phase exfoliation of their bulk form in water is a particularly fascinating concept. However, the current strategies for water-borne exfoliation exclusively employ stabilizers, such as surfactants, polymers, or inorganic salts, to minimize the extremely high surface energy of these nanosheets and stabilize them by steric repulsion. It is worth noting, however, that the remaining impurities inevitably bring about adverse effects to the ultimate performances of 2D materials. Here, a facile and green route to large-scale production of impurity-free aqueous solutions of WS 2 nanosheets is reported by direct exfoliation in water. Crucial parameters such as initial concentration, sonication time, centrifugation speed, and centrifugation time are systematically evaluated to screen out an optimized condition for scaling up. Statistics based on morphological characterization prove that substantial fraction (66%) of the obtained WS 2 nanosheets are one to five layers. X-ray diffraction and Raman characterizations reveal a high quality with few, if any, structural distortions. The water-borne exfoliation route opens up new opportunities for easy, clean processing of WS 2 -based film devices that may shine in the fields of, e.g., energy storage and functional nanocomposites owing to their excellent electrochemical, mechanical, and thermal properties. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Synthesis and Exfoliation of Discotic Zirconium Phosphates to Obtain Colloidal Liquid Crystals

Science.gov (United States)

Yu, Yi-Hsien; Wang, Xuezhen; Shinde, Abhijeet; Cheng, Zhengdong

2016-01-01

Due to their abundance in natural clay and potential applications in advanced materials, discotic nanoparticles are of interest to scientists and engineers. Growth of such anisotropic nanocrystals through a simple chemical method is a challenging task. In this study, we fabricate discotic nanodisks of zirconium phosphate [Zr(HPO4)2·H2O] as a model material using hydrothermal, reflux and microwave-assisted methods. Growth of crystals is controlled by duration time, temperature, and concentration of reacting species. The novelty of the adopted methods is that discotic crystals of size ranging from hundred nanometers to few micrometers can be obtained while keeping the polydispersity well within control. The layered discotic crystals are converted to monolayers by exfoliation with tetra-(n)-butyl ammonium hydroxide [(C4H9)4NOH, TBAOH]. Exfoliated disks show isotropic and nematic liquid crystal phases. Size and polydispersity of disk suspensions is highly important in deciding their phase behavior. PMID:27284765

Large-strain Soft Sensors Using Elastomers Blended with Exfoliated/Fragmented Graphite Particles

Energy Technology Data Exchange (ETDEWEB)

Park, Sungmin; Nam, Gyungmok; Kim, Jonghun; Yoon, Sang-Hee [Inha Univ., Incheon (Korea, Republic of)

2016-09-15

An elastic polymer (e.g., PDMS) blended with EFG particles is a promising conductive composite for fabricating soft sensors that can detect an object's deformation up to or more than 50 %. Here, we develop large-strain, sprayable soft sensors using a mixture of PDMS and EFG particles, which are used as a host elastomer and electrically conductive particles, respectively. A solution for a conductive composite mixture is prepared by the microwave-assisted graphite exfoliation, followed by ultrasonication-induced fragmentation of the exfoliated graphite and ultrasonic blending of PDMS and EFG. Using the prepared solutions for composite and pure PDMS, 1-, 2-, and 3-axis soft sensors are fabricated by airbrush stencil technique where composite mixture and pure PDMS are materials for sensing and insulating layers, respectively. We characterize the soft strain sensors after investigating the effect of PDMS/EFG wt % on mechanical compliance and electrical conductance of the conductive composite.

Pulmonary Embolism as the Initial Presentation of Testicular Carcinoma

Science.gov (United States)

Berber, Ilhami; Erkurt, Mehmet Ali; Ulutas, Ozkan; Ediz, Caner; Nizam, Ilknur; Kırıcı Berber, Nurcan; Unlu, Serkan; Koroglu, Reyhan; Koroglu, Mustafa; Akpolat, Nusret

2013-01-01

Objective. The risk of pulmonary embolism is well recognized as showing an increase in oncological patients. We report a case presenting with pulmonary embolism initially, which was then diagnosed with testicular cancer. Clinical Presentation and Intervention. A 25-year-old man was admitted to the emergency department with a complaint of dyspnoea. Thoracic tomography, lung ventilation/perfusion scintigraphy, and an increased D-dimer level revealed pulmonary embolism. For the aetiology of pulmonary embolism, a left orchiectomy was performed and the patient was diagnosed with a germinal cell tumour of the testicle. Conclusion. In this paper, we present a patient for whom pulmonary embolism was the initial presentation, and a germinal cell tumour was diagnosed later during the search for the aetiology. PMID:24383024

Abnormal pulmonary function and associated risk factors in children and adolescents with sickle cell anemia

Science.gov (United States)

Arteta, Manuel; Campbell, Andrew; Nouraie, Mehdi; Rana, Sohail; Onyekwere, Onyinye; Ensing, Gregory; Sable, Craig; Dham, Niti; Darbari, Deepika; Luchtman-Jones, Lori; Kato, Gregory J.; Gladwin, Mark T.; Castro, Oswaldo L.; Minniti, Caterina P.; Gordeuk, Victor R.

2015-01-01

Obstructive and restrictive pulmonary changes develop in children with sickle cell disease, but reports conflict as to the type of change that predominates. We prospectively performed spirometry, plethysmography and lung diffusing capacity in 146 children aged 7–20 years with hemoglobin SS or Sβ0-thalassemia. Nineteen percent of the patients had obstructive physiology as defined according to guidelines of the American Thoracic Society. In addition, 9% had restrictive physiology and 11% had abnormal but not categorized physiology. Increasing age, patient- or family-reported history of asthma or wheezing, and higher lactate dehydrogenase concentration were independent predictors of obstruction as reflected in lower FEV1/FVC. In conclusion, abnormal pulmonary function, most often obstructive, is common in children with hemoglobin SS and Sβ0-thalassemia. Full pulmonary function testing should be performed in children with hemoglobin SS or Sβ0 thalassemia, especially with history of asthma or wheezing and accentuated elevations in hemolytic markers. PMID:24309610

Terapia celular em doenças pulmonares: existem perspectivas? Cell therapy in pulmonary diseases: are there perspectives?

Directory of Open Access Journals (Sweden)

João T. Ribeiro-Paes

2009-05-01

cells in the treatment of diseases. Although the number of scientific reports involving lung and cell therapy in humans is not expressive, there are consistent data, both in humans and animal models. Experiments show the migration of bone marrow stem cells to the lung, in different situations. These results provide the experimental basis for the use of stem cells in the regeneration of the lung tissue in animal models. In our laboratory, several projects have been conducted aiming to evaluate the pulmonary response (morphological and functional to treatment with adult stem cells in mice with experimentally induced chronic obstructive pulmonary disease. The results obtained, together with those from other research groups, allow us to consider the possibility of application, in the near future, of cell therapy in chronic obstructive pulmonary disease patients. For another disease, cystic fibrosis, cell therapy shows particular aspects in relation to other chronic degenerative pulmonary diseases. In this pathology, there are interesting and promising advances, however, the results are incipient and, thus, it must be said that the association between genetic and cell therapy appears to be a possibility, but still far from being consolidated and incorporated as a safe and effective therapeutic alternative in cystic fibrosis. On the other hand, based on the results obtained in experimental models, it is possible to postulate that cell therapy with hematopoietic stem cells (or from other sources brings consistent application perspectives in several other human pulmonary diseases, especially in chronic obstructive pulmonary disease.

Aqueous Exfoliation of Graphite into Graphene Assisted by Sulfonyl Graphene Quantum Dots for Photonic Crystal Applications.

Science.gov (United States)

Zeng, Minxiang; Shah, Smit A; Huang, Dali; Parviz, Dorsa; Yu, Yi-Hsien; Wang, Xuezhen; Green, Micah J; Cheng, Zhengdong

2017-09-13

We investigate the π-π stacking of polyaromatic hydrocarbons (PAHs) with graphene surfaces, showing that such interactions are general across a wide range of PAH sizes and species, including graphene quantum dots. We synthesized a series of graphene quantum dots with sulfonyl, amino, and carboxylic functional groups and employed them to exfoliate and disperse pristine graphene in water. We observed that sulfonyl-functionalized graphene quantum dots were able to stabilize the highest concentration of graphene in comparison to other functional groups; this is consistent with prior findings by pyrene. The graphene nanosheets prepared showed excellent colloidal stability, indicating great potential for applications in electronics, solar cells, and photonic displays which was demonstrated in this work.

Study on the diagnostic value of plasma Adrenomedullin (AM) levels determination for differentiation of pulmonary cancer from pulmonary tuberculosis

International Nuclear Information System (INIS)

Yu Hua; Sun Shuhong; Xu Shuhua; Zhu Wenru; Yu Hui

2005-01-01

Objective: To explore the relationship between plasma adrenomedullin (AM) levels and pulmonary cancer as well as the diagnostic value of AM levels determination for differentiation of pulmonary cancer from pulmonary tuberculosis. Methods: Plasma levels of AM in patients with pulmonary cancer (n=43), pulmonary tuberculosis (n=43) and 43 controls were determined with RIA. Results: Plasma levels of AM (98.46 ± 29.28 ng/ml) in patients with pulmonary cancer were significantly higher than those in patients with pulmonary tuberculosis (61.46 ± 19.57 ng/ml) as well as those in controls (40.22 ± 8.23 ng/ml) (both P<0.01). Levels in patients with small cell carcinoma were significantly lower than those in patients with adenocarcinoma and squamous cell carcinoma (both P<0.05). Positive correlation existed between the plasma levels of AM and the severity (grading 1 to 4) of the disease (P<0.05). Conclusion: Adrenomedullin could be regarded as a valuable plasma marker for differentiating lung cancer from tuberculosis. The plasma AM levels might be able to reflect the severity and predict the prognosis of the disease. Besides, high AM levels might suggest a tentative diagnosis of lung cancer in patients without pathologic evidence. (authors)

Liquid-phase exfoliated graphene self-assembled films: Low-frequency noise and thermal-electric characterization

International Nuclear Information System (INIS)

Tubon Usca, G.; Hernandez-Ambato, J.; Pace, C.; Caputi, L.S.; Tavolaro, A.

2016-01-01

Highlights: • Graphene was exfoliated in liquid phase also in the presence of zeolite 4A. • Films were obtained by drop-casting. • SEM, Raman, low-frequency noise and thermal electric measurements show that the presence of zeolite improves the quality of the FLG films. - Abstract: In few years, graphene has become a revolutionary material, leading not only to applications in various fields such as electronics, medicine and environment, but also to the production of new types of 2D materials. In this work, Liquid Phase Exfoliation (LPE) was applied to natural graphite by brief sonication or mixer treatment in suitable solvents, in order to produce Few Layers Graphene (FLG) suspensions. Additionally, zeolite 4A (Z4A) was added during the production of FLG flakes-based inks, with the aim of aiding the exfoliation process. Conductive films were obtained by drop casting three types of suspensions over Al 2 O 3 substrates with interdigitated electrodes, with total channel surface of 1.39 mm 2 . The morphology characterization resulted in the verification of the presence of thin self-assembled flakes. Raman studies gave evidence of 4 to 10 layers graphene flakes. Electrical measurements were performed to state the Low-Frequency Noise and Thermal-Electric characteristics of the samples. We observe interesting relations between sample preparation procedures and electrical properties.

Chemical warfare agent and biological toxin-induced pulmonary toxicity: could stem cells provide potential therapies?

Science.gov (United States)

Angelini, Daniel J; Dorsey, Russell M; Willis, Kristen L; Hong, Charles; Moyer, Robert A; Oyler, Jonathan; Jensen, Neil S; Salem, Harry

2013-01-01

Chemical warfare agents (CWAs) as well as biological toxins present a significant inhalation injury risk to both deployed warfighters and civilian targets of terrorist attacks. Inhalation of many CWAs and biological toxins can induce severe pulmonary toxicity leading to the development of acute lung injury (ALI) as well as acute respiratory distress syndrome (ARDS). The therapeutic options currently used to treat these conditions are very limited and mortality rates remain high. Recent evidence suggests that human stem cells may provide significant therapeutic options for ALI and ARDS in the near future. The threat posed by CWAs and biological toxins for both civilian populations and military personnel is growing, thus understanding the mechanisms of toxicity and potential therapies is critical. This review will outline the pulmonary toxic effects of some of the most common CWAs and biological toxins as well as the potential role of stem cells in treating these types of toxic lung injuries.

An ultrahigh pressure homogenization technique for easily exfoliating few-layer phosphorene from bulk black phosphorus

Science.gov (United States)

Guan, Qing-Qing; Zhou, Hua-Jing; Ning, Ping; Lian, Pei-Chao; Wang, Bo; He, Liang; Chai, Xin-Sheng

2018-05-01

We have developed an easy and efficient method for exfoliating few-layer sheets of black phosphorus (BP) in N-methyl-2-pyrrolidone, using ultra-high pressure homogenization (UPH). The BP was first exfoliated into sheets that were a few atomic layers thick, using a homogenizer for only 30 min. Next, a double centrifugation procedure was used to separate the material into few-layer nanosheets that were examined by X-ray diffraction, atomic force microscopy (AFM), transmission electron microscopy (TEM), high-angle annular dark field scanning transmission electron microscopy (HAADF-STEM), and energy-dispersive X-ray (EDX) spectroscopy. The results show that the products are specimens of phosphorene that are only a few-layer thick.

Bcl-2 silencing attenuates hypoxia-induced apoptosis resistance in pulmonary microvascular endothelial cells.

Science.gov (United States)

Cao, Yongmei; Jiang, Zhen; Zeng, Zhen; Liu, Yujing; Gu, Yuchun; Ji, Yingying; Zhao, Yupeng; Li, Yingchuan

2016-01-01

Pulmonary arterial hypertension (PAH) is a life-threatening disorder that ultimately causes heart failure. While the underlying causes of this condition are not well understood, previous studies suggest that the anti-apoptotic nature of pulmonary microvascular endothelial cells (PMVECs) in hypoxic environments contributes to PAH pathogenesis. In this study, we focus on the contribution of Bcl-2 and hypoxia response element (HRE) to apoptosis-resistant endothelial cells and investigate the mechanism. PMVECs obtained from either normal rats or apoptosis-resistant PMVECs obtained from PAH rats were transduced with recombinant lentiviral vectors carrying either Bcl-2-shRNA or HRE combined Bcl-2-shRNA, and then cultured these cells for 24 h under hypoxic (5% O2) or normoxic (21% O2) conditions. In normal PMVECs, Bcl-2-shRNA or HRE combined with Bcl-2-shRNA transduction successfully decreased Bcl-2 expression, while increasing apoptosis as well as caspase-3 and P53 expression in a normoxic environment. In a hypoxic environment, the effects of Bcl-2-shRNA treatment on cell apoptosis, and on Bcl-2, caspase-3, P53 expression were significantly suppressed. Conversely, HRE activation combined with Bcl-2-shRNA transduction markedly enhanced cell apoptosis and upregulated caspase-3 and P53 expression, while decreasing Bcl-2 expression. Furthermore, in apoptosis-resistant PMVECs, HRE-mediated Bcl-2 silencing effectively enhanced cell apoptosis and caspase-3 activity. The apoptosis rate was significantly depressed when Lv-HRE-Bcl-2-shRNA was combined with Lv-P53-shRNA or Lv-caspase3-shRNA transduction in a hypoxic environment. These results suggest that HRE-mediated Bcl-2 inhibition can effectively attenuate hypoxia-induced apoptosis resistance in PMVECs by downregulating Bcl-2 expression and upregulating caspase-3 and P53 expression. This study therefore reveals critical insight into potential therapeutic targets for treating PAH.

Dextromethorphan mediated bitter taste receptor activation in the pulmonary circuit causes vasoconstriction.

Science.gov (United States)

Upadhyaya, Jasbir D; Singh, Nisha; Sikarwar, Anurag S; Chakraborty, Raja; Pydi, Sai P; Bhullar, Rajinder P; Dakshinamurti, Shyamala; Chelikani, Prashen

2014-01-01

Activation of bitter taste receptors (T2Rs) in human airway smooth muscle cells leads to muscle relaxation and bronchodilation. This finding led to our hypothesis that T2Rs are expressed in human pulmonary artery smooth muscle cells and might be involved in regulating the vascular tone. RT-PCR was performed to reveal the expression of T2Rs in human pulmonary artery smooth muscle cells. Of the 25 T2Rs, 21 were expressed in these cells. Functional characterization was done by calcium imaging after stimulating the cells with different bitter agonists. Increased calcium responses were observed with most of the agonists, the largest increase seen for dextromethorphan. Previously in site-directed mutational studies, we have characterized the response of T2R1 to dextromethorphan, therefore, T2R1 was selected for further analysis in this study. Knockdown with T2R1 specific shRNA decreased mRNA levels, protein levels and dextromethorphan-induced calcium responses in pulmonary artery smooth muscle cells by up to 50%. To analyze if T2Rs are involved in regulating the pulmonary vascular tone, ex vivo studies using pulmonary arterial and airway rings were pursued. Myographic studies using porcine pulmonary arterial and airway rings showed that stimulation with dextromethorphan led to contraction of the pulmonary arterial and relaxation of the airway rings. This study shows that dextromethorphan, acting through T2R1, causes vasoconstrictor responses in the pulmonary circuit and relaxation in the airways.

Investigation of exfoliation joints in Navajo sandstone at the Zion National Park and in granite at the Yosemite National Park by tectonofractographic techniques

Energy Technology Data Exchange (ETDEWEB)

Bahat, D.; Grossenbacher, K.; Karasaki, K.

1995-04-01

Tectonofractographic techniques have been applied to the study of joint exfoliation in the Navajo sandstone at Zion National Park and in the granite at Yosemite National Park. New types of fracture surface morphologies have been observed which enabled the discerning of incipient joints and consequent fracture growth in these rocks. Incipient jointing in the sandstone is mostly manifested by elliptical and circular fractures (meters to tens meters across) initiating from independent origins. They interfere with each other and grow to larger circular fractures producing exfoliation surfaces up to hundreds of meters across. Less frequently, series of large concentric undulations demonstrate the propagation of a large fracture front producing exfoliation from an individual origin. One such fracture front reveals refraction of undulations at a layer boundary. Certain en echelon fringes surround the joint mirror plane with well defined rims of en echelons and hackles which enable the determination of the tensile fracture stress, {sigma}f. Arches in Zion National Park are ubiquitous in shape and size, revealing stages in their evolution by a mechanical process, which was associated with exfoliation, but independent of local faulting. Exfoliation and arching mostly occurred on vertical surfaces of N-NNW and NE sets of prominent joints, but there are also deviations from this general trend. In Yosemite National Park large exfoliations (hundreds of meters in size) developed on the El Capitan cliff by the interaction and merging of many previous smaller incipient joints that vary in size from meters to tens of meter.

Inflammation responses in patients with pulmonary tuberculosis in an intensive care unit

Science.gov (United States)

Liu, Qiu-Yue; Han, Fen; Pan, Li-Ping; Jia, Hong-Yan; Li, Qi; Zhang, Zong-De

2018-01-01

Pulmonary tuberculosis caused by Mycobacterium tuberculosis remains a global problem. Inflammatory responses are the primary characteristics of patients with pulmonary tuberculosis in intensive care units (ICU). The aim of the present study was to investigate the clinical importance of inflammatory cells and factors for patients with pulmonary tuberculosis in ICU. A total of 124 patients with pulmonary tuberculosis in ICU were recruited for the present study. The inflammatory responses in patients with pulmonary tuberculosis in ICU were examined by changes in inflammatory cells and factors in the serum. The results indicated that serum levels of lymphocytes, plasma cells, granulocytes and monocytes were increased in patients with pulmonary tuberculosis in ICU compared with healthy controls. The serum levels of inflammatory factors interleukin (IL)-1, IL-6, IL-10, IL-12, and IL-4 were upregulated in patients with pulmonary tuberculosis in ICU. Lower plasma concentrations of IL-2, IL-15 and interferon-γ were detected in patients with pulmonary tuberculosis compared with healthy controls. It was demonstrated that high mobility group box-1 protein expression levels were higher in the serum of patients with pulmonary tuberculosis compared with healthy controls. Notably, an imbalance of T-helper cell (Th)1/Th2 cytokines was observed in patients with pulmonary tuberculosis. Pulmonary tuberculosis caused by M. tuberculosis also upregulated expression of matrix metalloproteinase (MMP)-1 and MMP-9 in hPMCs. In conclusion, these outcomes demonstrated that inflammatory responses and inflammatory factors are associated with the progression of pulmonary tuberculosis, suggesting that inhibition of inflammatory responses and inflammatory factors may be beneficial for the treatment of patients with pulmonary tuberculosis in ICU. PMID:29456674

Self-Assembled BN and BCN Quantum Dots Obtained from High Intensity Ultrasound Exfoliated Nanosheets

Czech Academy of Sciences Publication Activity Database

Štengl, Václav; Henych, Jiří; Kormunda, M.

2014-01-01

Roč. 6, č. 6 (2014), s. 1106-1116 ISSN 1947-2935 Institutional support: RVO:61388980 Keywords : Ultrasound * Exfoliation * BN * BCN * Quantum Dots Subject RIV: CA - Inorganic Chemistry Impact factor: 2.598, year: 2014

Electromagnetic properties and performance of exfoliated graphite (EG) - thermoplastic polyurethane (TPU) nanocomposites at microwaves

Czech Academy of Sciences Publication Activity Database

Valentini, M.; Piana, Francesco; Pionteck, J.; Lamastra, F. R.; Nanni, F.

2015-01-01

Roč. 114, 19 June (2015), s. 26-33 ISSN 0266-3538 Institutional support: RVO:61389013 Keywords : exfoliated graphite * functional composites * nano composites Subject RIV: CD - Macromolecular Chemistry Impact factor: 3.897, year: 2015

Pulmonary lymphangioleiomyomatosis

International Nuclear Information System (INIS)

Shawki, Hilal B.; Muhammad, Shakir M.; Reda, Amal N.; Abdulla, Thair S.; Ardalan, Delaram M.

2007-01-01

A 38-year-old Iraqi female, presented with one-year history of exertional dyspnea and exercise intolerance, without systemic or constitutional symptoms. Clinical examination revealed bilateral basal crackles with signs suggestive of left side pleural effusion, chest x-ray showed left sided pleural effusion, and diffuse bilateral basal pulmonary shadowing. Her biochemical analysis, hematological tests, electrocardiogram and echocardiography were normal, aspiration of the fluid revealed a chylothorax, the radiological shadowing was proved by computed tomography scan of the chest to be diffuse cystic lesions involving mostly lower lobes. Open lung biopsy showed dilated lymphatic vessels with surrounding inflammatory cells and smooth muscle fibers consistently with the diagnosis of pulmonary lymphangioleiomyomatosis. (author)

Environmentally benign graphite intercalation compound composition for exfoliated graphite, flexible graphite, and nano-scaled graphene platelets

Science.gov (United States)

Zhamu, Aruna; Jang, Bor Z.

2014-06-17

A carboxylic-intercalated graphite compound composition for the production of exfoliated graphite, flexible graphite, or nano-scaled graphene platelets. The composition comprises a layered graphite with interlayer spaces or interstices and a carboxylic acid residing in at least one of the interstices, wherein the composition is prepared by a chemical oxidation reaction which uses a combination of a carboxylic acid and hydrogen peroxide as an intercalate source. Alternatively, the composition may be prepared by an electrochemical reaction, which uses a carboxylic acid as both an electrolyte and an intercalate source. Exfoliation of the invented composition does not release undesirable chemical contaminants into air or drainage.

Dyspnea, pulmonary function and exercise capacity in adult Saudi patients with sickle cell disease

International Nuclear Information System (INIS)

Alameri, Hatem F.; Alem, A.; Al-Momen, A.; Kardas, W.; Owais, M.; Jehangir, A.

2008-01-01

Objective was to examine pulmonary function, dyspnea, and exercise capacity in adult Saudi patients with sickle cell disease (SCD) patients. The patients were recruited from the hematology clinic at King Khalid University Hospital in Riyadh from January to December 2005. The study involved 39 patients with stable SCD 20 women and 19 men, with a mean age of 22.7+/- 7.1 years, hemoglobin level of 95.5+/-14.6g/L and hemoglobin F level of 13.7+/08.6. Patients underwent pulmonary function tests PFT forced expiratory volume in first second [FEV1], forced vital capacity [FVC], and diffusion capacity of carbon monoxide [DLco] data are presented as a percentage of the normal prediction, a 6- minute walk test 6MWT and echocardiography. Dyspnea was assessed using the Borg score. The 6MWT data were compared to body mass index matched healthy controls. Forty-one percent of SCD patients had mild dyspnea at rest and this increased to 61% at the end of the 6MWT. Pulmonary function tests were abnormal in 51%, 36% of patients had a restrictive pattern, 10% had isolated decrease in DLco and 5% had a mixed restrictive-obstrutive pattern. The 6MWD was shorter in SCD patients compared to the controls 368+/-67 versus 407+/-47m, p=0.005. No hematological variables correlated with outcome variables. Chronic pulmonary complications in adult Saudi SCD patients are relatively mild but common. Pulmonary function in these patients differs from that published for African-origin SCD patients. The difference may reflect a different natural history of SCD in the 2 populations. (author)

Detection of pulmonary metastases in a patient with synovial cell sarcoma using In-111 labeled monoclonal antibody 19-24

International Nuclear Information System (INIS)

Swift, J.E.; Blend, M.J.; Bekerman, C.; Das Gupta, T.K.; Greager, J.A.

1990-01-01

A 35-year-old man was diagnosed in 1984 as having a synovial cell sarcoma of his right wrist without evidence of metastatic spread. The patient underwent regional hyperthermic chemoperfusion, wide-field excision, post-operative radiation therapy and systemic adjuvant chemotherapy. In 1986 and in 1987, because of new lesions found on chest radiographs, the patient underwent bilateral staging thoracotomies with resection of pulmonary metastases, followed by chemotherapy and radiotherapy. Later in 1987, a chest radiograph showed a large left hilar mass and multiple bilateral pulmonary nodules. Computerized tomography of the chest demonstrated a left hilar mass and two nodules in the right lower lung, raising the possibility of recurrent pulmonary metastatic cancer. As a diagnostic procedure, In-111 labeled monoclonal antibody (Mab) 19-24, produced against a human malignant fibrous histiocytoma, was infused intravenously, and 48-hour images revealed focal areas of increased uptake corresponding to the lesions seen on CT. At surgery, the lesions were confirmed to be synovial cell sarcoma. Imaging with Mabs specific for sarcoma may be particularly useful in sarcoma patients in whom there is clinical uncertainty regarding the nature of pulmonary lesions. In this case, the Mab was useful in distinguishing tumor deposits from postsurgical scarring and helped to guide subsequent surgery and treatment

Production of exfoliative toxin by isolates of Staphylococcus hyicus from different countries

DEFF Research Database (Denmark)

Andresen, Lars Ole

2005-01-01

A total of 218 isolates of Staphylococcus hyicus from pigs in eight countries (Belgium, Croatia, Germany, Japan, Korea, Slovenia, the UK and the USA) and 44 isolates from other animals in Belgium, India, Japan and the USA were examined for the genes encoding the exfoliative toxins ExhA, ExhB, Exhc...

Glycyrrhizic acid alleviates bleomycin-induced pulmonary fibrosis in rats

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Lili eGao

2015-10-01

Full Text Available Idiopathic pulmonary fibrosis is a progressive and lethal form of interstitial lung disease that lacks effective therapies at present. Glycyrrhizic acid (GA, a natural compound extracted from a traditional Chinese herbal medicine Glycyrrhiza glabra, was recently reported to benefit lung injury and liver fibrosis in animal models, yet whether GA has a therapeutic effect on pulmonary fibrosis is unknown. In this study, we investigated the potential therapeutic effect of GA on pulmonary fibrosis in a rat model with bleomycin (BLM-induced pulmonary fibrosis. The results indicated that GA treatment remarkably ameliorated BLM-induced pulmonary fibrosis and attenuated BLM-induced inflammation, oxidative stress, epithelial-mesenchymal transition and activation of tansforming growth factor-beta signaling pathway in the lungs. Further, we demonstrated that GA treatment inhibited proliferation of 3T6 fibroblast cells, induced cell cycle arrest and promoted apoptosis in vitro, implying that GA-mediated suppression of fibroproliferation may contribute to the anti-fibrotic effect against BLM-induced pulmonary fibrosis. In summary, our study suggests a therapeutic potential of GA in the treatment of pulmonary fibrosis.

Effects of mineral trioxide aggregate, BiodentineTM and calcium hydroxide on viability, proliferation, migration and differentiation of stem cells from human exfoliated deciduous teeth

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Leandro Borges Araújo

2018-02-01

Full Text Available Abstract Objective: The aim of the study was to evaluate the effects of the capping materials mineral trioxide aggregate (MTA, calcium hydroxide (CH and BiodentineTM (BD on stem cells from human exfoliated deciduous teeth (SHED in vitro. Material and Methods: SHED were cultured for 1 – 7 days in medium conditioned by incubation with MTA, BD or CH (1 mg/mL, and tested for viability (MTT assay and proliferation (SRB assay. Also, the migration of serum-starved SHED towards conditioned media was assayed in companion plates, with 8 μm-pore-sized membranes, for 24 h. Gene expression of dentin matrix protein-1 (DMP-1 was evaluated by reverse-transcription polymerase chain reaction. Regular culture medium with 10% FBS (without conditioning and culture medium supplemented with 20% FBS were used as controls. Results: MTA, CH and BD conditioned media maintained cell viability and allowed continuous SHED proliferation, with CH conditioned medium causing the highest positive effect on proliferation at the end of the treatment period (compared with BD and MTA (p<0.05. In contrast, we observed increased SHED migration towards BD and MTA conditioned media (compared with CH (p<0.05. A greater amount of DMP-1 gene was expressed in MTA group compared with the other groups from day 7 up to day 21. Conclusion: Our results show that the three capping materials are biocompatible, maintain viability and stimulate proliferation, migration and differentiation in a key dental stem cell population.

Secretory proteins of the pulmonary extracellular lining

International Nuclear Information System (INIS)

Gupta, R.P.; Patton, S.E.; Eddy, M.; Smits, H.L.; Jetten, A.M.; Nettesheim, P.; Hook, G.E.R.

1986-01-01

The objective of this investigation was to identify proteins in the pulmonary extracellular lining (EL) that are secreted by cells of the pulmonary epithelium. Pulmonary lavage effluents from the lungs of rabbits were centrifuged to remove all cells and particulate materials. Serum proteins were removed by repeatedly passing concentrated lavage effluent fluid through an affinity column containing IgG fraction of goat anti-rabbit (whole serum) antiserum bound to Sepharose-4B. Nonserum proteins accounted for 21.3 +/- 10.3% of the total soluble proteins in pulmonary lavage effluents. Serum free lavage effluents (SFL) contained 25 identifiable proteins as determined by using SDS-PAGE under reducing conditions. Of these proteins approximately 73% was accounted for by a single protein with MW of 66 kd. The secretory nature of the proteins present in SFL was investigated by studying the incorporation of 35 S-methionine into proteins released by lung slices and trachea followed by SDS-PAGE and autoradiography. Many, but not all proteins present in SFL were identified as proteins secreted by pulmonary tissues. The major secretory proteins appeared to have MWs of 59, 53, 48, 43, 24, 14, and 6 kd under reducing conditions. These data demonstrate the presence of several proteins in the pulmonary extracellular lining that appear to be secreted by the pulmonary epithelium

Impact of pulmonary rehabilitation on postoperative complications in patients with lung cancer and chronic obstructive pulmonary disease.

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Saito, Hajime; Hatakeyama, Kazutoshi; Konno, Hayato; Matsunaga, Toshiki; Shimada, Yoichi; Minamiya, Yoshihiro

2017-09-01

Given the extent of the surgical indications for pulmonary lobectomy in breathless patients, preoperative care and evaluation of pulmonary function are increasingly necessary. The aim of this study was to assess the contribution of preoperative pulmonary rehabilitation (PR) for reducing the incidence of postoperative pulmonary complications in non-small cell lung cancer (NSCLC) patients with chronic obstructive pulmonary disease (COPD). The records of 116 patients with COPD, including 51 patients who received PR, were retrospectively analyzed. Pulmonary function testing, including slow vital capacity (VC) and forced expiratory volume in one second (FEV 1 ), was obtained preoperatively, after PR, and at one and six months postoperatively. The recovery rate of postoperative pulmonary function was standardized for functional loss associated with the different resected lung volumes. Propensity score analysis generated matched pairs of 31 patients divided into PR and non-PR groups. The PR period was 18.7 ± 12.7 days in COPD patients. Preoperative pulmonary function was significantly improved after PR (VC 5.3%, FEV 1 5.5%; P pulmonary complications after pulmonary lobectomy (odds ratio 18.9, 16.1, and 13.9, respectively; P pulmonary function after lobectomy in the early period, and may decrease postoperative pulmonary complications. © 2017 The Authors. Thoracic Cancer published by China Lung Oncology Group and John Wiley & Sons Australia, Ltd.

Chemical exfoliation and optical characterization of threading-dislocation-free gallium-nitride ultrathin nanomembranes

KAUST Repository

Elafandy, Rami T.

2014-11-13

Semiconductor nanostructures have generated tremendous scientific interests as well as practical applications stemming from the engineering of low dimensional physics phenomena. Unlike 0D and 1D nanostructures, such as quantum dots and nanowires, respectively, 2D structures, such as nanomembranes, are unrivalled in their scalability for high yield manufacture and are less challenging in handling with the current transfer techniques. Furthermore, due to their planar geometry, nanomembranes are compatible with the current complementary metal oxide semiconductor (CMOS) technology. Due to these superior characteristics, there are currently different techniques in exfoliating nanomembranes with different crystallinities, thicknesses and compositions. In this work we demonstrate a new facile technique of exfoliating gallium nitride (GaN) nanomembranes with novel features, namely with the non-radiative cores of their threading-dislocations (TDs) being etched away. The exfoliation process is based on engineering the gallium vacancy (VGa) density during the GaN epitaxial growth with subsequent preferential etching. Based on scanning and transmission electron microscopies, as well as micro-photoluminescence measurements, a model is proposed to uncover the physical processes underlying the formation of the nanomembranes. Raman measurements are also performed to reveal the internal strain within the nanomembranes. After transferring these freely suspended 25 nm thin GaN nanomembranes to other substrates, we demonstrate the temperature dependence of their bandgap by photoluminescence technique, in order to shed light on the internal carrier dynamics. © (2014) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.

Dextromethorphan mediated bitter taste receptor activation in the pulmonary circuit causes vasoconstriction.

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Jasbir D Upadhyaya

Full Text Available Activation of bitter taste receptors (T2Rs in human airway smooth muscle cells leads to muscle relaxation and bronchodilation. This finding led to our hypothesis that T2Rs are expressed in human pulmonary artery smooth muscle cells and might be involved in regulating the vascular tone. RT-PCR was performed to reveal the expression of T2Rs in human pulmonary artery smooth muscle cells. Of the 25 T2Rs, 21 were expressed in these cells. Functional characterization was done by calcium imaging after stimulating the cells with different bitter agonists. Increased calcium responses were observed with most of the agonists, the largest increase seen for dextromethorphan. Previously in site-directed mutational studies, we have characterized the response of T2R1 to dextromethorphan, therefore, T2R1 was selected for further analysis in this study. Knockdown with T2R1 specific shRNA decreased mRNA levels, protein levels and dextromethorphan-induced calcium responses in pulmonary artery smooth muscle cells by up to 50%. To analyze if T2Rs are involved in regulating the pulmonary vascular tone, ex vivo studies using pulmonary arterial and airway rings were pursued. Myographic studies using porcine pulmonary arterial and airway rings showed that stimulation with dextromethorphan led to contraction of the pulmonary arterial and relaxation of the airway rings. This study shows that dextromethorphan, acting through T2R1, causes vasoconstrictor responses in the pulmonary circuit and relaxation in the airways.

Electrochemically cathodic exfoliation of graphene sheets in room temperature ionic liquids N-butyl, methylpyrrolidinium bis(trifluoromethylsulfonyl)imide and their electrochemical properties

International Nuclear Information System (INIS)

Yang, Yingchang; Lu, Fang; Zhou, Zhou; Song, Weixin; Chen, Qiyuan; Ji, Xiaobo

2013-01-01

Graphical abstract: Electrochemically cathodic exfoliation of graphite into few-layer graphene sheets in room temperature ionic liquids (RTILs) N-butyl, methylpyrrolidinium bis(trifluoromethylsulfonyl)-imide (BMPTF 2 N). -- Highlights: • Few-layer graphene sheets were prepared through electrochemically cathodic exfoliation in room temperature ionic liquids. • The mechanism of cathodic exfoliation in ionic liquids was proposed. • The derived activated graphene sheets show enhanced electrochemical properties. -- Abstract: Electrochemically cathodic exfoliation in room temperature ionic liquids N-butyl, methylpyrrolidinium bis(trifluoromethylsulfonyl)-imide (BMPTF 2 N) has been developed for few-layer graphene sheets, demonstrating low levels of oxygen (2.7 at% of O) with a nearly perfect structure (I D /I G 2 N involves the intercalation of ionic liquids cation [BMP] + under highly negatively charge followed by graphite expansion. Porous activated graphene sheets were also obtained by activation of graphene sheets in KOH. Transmission electron microscopy, X-ray photoelectron spectroscopy and Raman spectroscopy were used to characterize these graphene materials. The electrochemical performances of the graphene sheets and porous activated graphene sheets for lithium-ion battery anode materials were evaluated using cyclic voltammetry, galvanostatic charge–discharge cycling, and electrochemical impedance spectroscopy

Chronic hypoxia promotes pulmonary artery endothelial cell proliferation through H2O2-induced 5-lipoxygenase.

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Kristi M Porter

Full Text Available Pulmonary Hypertension (PH is a progressive disorder characterized by endothelial dysfunction and proliferation. Hypoxia induces PH by increasing vascular remodeling. A potential mediator in hypoxia-induced PH development is arachidonate 5-Lipoxygenase (ALOX5. While ALOX5 metabolites have been shown to promote pulmonary vasoconstriction and endothelial cell proliferation, the contribution of ALOX5 to hypoxia-induced proliferation remains unknown. We hypothesize that hypoxia exposure stimulates HPAEC proliferation by increasing ALOX5 expression and activity. To test this, human pulmonary artery endothelial cells (HPAEC were cultured under normoxic (21% O2 or hypoxic (1% O2 conditions for 24-, 48-, or 72 hours. In a subset of cells, the ALOX5 inhibitor, zileuton, or the 5-lipoxygenase activating protein inhibitor, MK-886, was administered during hypoxia exposure. ALOX5 expression was measured by qRT-PCR and western blot and HPAEC proliferation was assessed. Our results demonstrate that 24 and 48 hours of hypoxia exposure have no effect on HPAEC proliferation or ALOX5 expression. Seventy two hours of hypoxia significantly increases HPAEC ALOX5 expression, hydrogen peroxide (H2O2 release, and HPAEC proliferation. We also demonstrate that targeted ALOX5 gene silencing or inhibition of the ALOX5 pathway by pharmacological blockade attenuates hypoxia-induced HPAEC proliferation. Furthermore, our findings indicate that hypoxia-induced increases in cell proliferation and ALOX5 expression are dependent on H2O2 production, as administration of the antioxidant PEG-catalase blocks these effects and addition of H2O2 to HPAEC promotes proliferation. Overall, these studies indicate that hypoxia exposure induces HPAEC proliferation by activating the ALOX5 pathway via the generation of H2O2.

The increase of microRNA-21 during lung fibrosis and its contribution to epithelial-mesenchymal transition in pulmonary epithelial cells.

Science.gov (United States)

Yamada, Mitsuhiro; Kubo, Hiroshi; Ota, Chiharu; Takahashi, Toru; Tando, Yukiko; Suzuki, Takaya; Fujino, Naoya; Makiguchi, Tomonori; Takagi, Kiyoshi; Suzuki, Takashi; Ichinose, Masakazu

2013-09-24

The excess and persistent accumulation of fibroblasts due to aberrant tissue repair results in fibrotic diseases such as idiopathic pulmonary fibrosis. Recent reports have revealed significant changes in microRNAs during idiopathic pulmonary fibrosis and evidence in support of a role for microRNAs in myofibroblast differentiation and the epithelial-mesenchymal transition in the context of fibrosis. It has been reported that microRNA-21 is up-regulated in myofibroblasts during fibrosis and promotes transforming growth factor-beta signaling by inhibiting Smad7. However, expression changes in microRNA-21 and the role of microRNA-21 in epithelial-mesenchymal transition during lung fibrosis have not yet been defined. Lungs from saline- or bleomycin-treated C57BL/6 J mice and lung specimens from patients with idiopathic pulmonary fibrosis were analyzed. Enzymatic digestions were performed to isolate single lung cells. Lung epithelial cells were isolated by flow cytometric cell sorting. The expression of microRNA-21 was analyzed using both quantitative PCR and in situ hybridization. To induce epithelial-mesenchymal transition in culture, isolated mouse lung alveolar type II cells were cultured on fibronectin-coated chamber slides in the presence of transforming growth factor-β, thus generating conditions that enhance epithelial-mesenchymal transition. To investigate the role of microRNA-21 in epithelial-mesenchymal transition, we transfected cells with a microRNA-21 inhibitor. Total RNA was isolated from the freshly isolated and cultured cells. MicroRNA-21, as well as mRNAs of genes that are markers of alveolar epithelial or mesenchymal cell differentiation, were quantified using quantitative PCR. The lung epithelial cells isolated from the bleomycin-induced lung fibrosis model system had decreased expression of epithelial marker genes, whereas the expression of mesenchymal marker genes was increased. MicroRNA-21 was significantly upregulated in isolated lung epithelial

Two-stage preparation of magnetic sorbent based on exfoliated graphite with ferrite phases for sorption of oil and liquid hydrocarbons from the water surface

Science.gov (United States)

Pavlova, Julia A.; Ivanov, Andrei V.; Maksimova, Natalia V.; Pokholok, Konstantin V.; Vasiliev, Alexander V.; Malakho, Artem P.; Avdeev, Victor V.

2018-05-01

Due to the macropore structure and the hydrophobic properties, exfoliated graphite (EG) is considered as a perspective sorbent for oil and liquid hydrocarbons from the water surface. However, there is the problem of EG collection from the water surface. One of the solutions is the modification of EG by a magnetic compound and the collection of EG with sorbed oil using the magnetic field. In this work, the method of the two-stage preparation of exfoliated graphite with ferrite phases is proposed. This method includes the impregnation of expandable graphite in the mixed solution of iron (III) chloride and cobalt (II) or nickel (II) nitrate in the first stage and the thermal exfoliation of impregnated expandable graphite with the formation of exfoliated graphite containing cobalt and nickel ferrites in the second stage. Such two-stage method makes it possible to obtain the sorbent based on EG modified by ferrimagnetic phases with high sorption capacity toward oil (up to 45-51 g/g) and high saturation magnetization (up to 42 emu/g). On the other hand, this method allows to produce the magnetic sorbent in a short period of time (up to 10 s) during which the thermal exfoliation is carried out in the air atmosphere.

Fabrication of single phase 2D homologous perovskite microplates by mechanical exfoliation

Science.gov (United States)

Li, Junze; Wang, Jun; Zhang, Yingjun; Wang, Haizhen; Lin, Gaoming; Xiong, Xuan; Zhou, Weihang; Luo, Hongmei; Li, Dehui

2018-04-01

The two-dimensional (2D) Ruddlesden-Popper type perovskites have attracted intensive interest for their great environmental stability and various potential optoelectronic applications. Fundamental understanding of the photophysical and electronic properties of the 2D perovskites with pure single phase is essential for improving the performance of the optoelectronic devices and designing devices with new architectures. Investigating the optical and electronic properties of these materials with pure single phase is required to obtain pure single phase 2D perovskites. Here, we report on an alternative approach to fabricate (C4H9NH3)2(CH3NH3) n-1Pb n I3n+1 microplates with pure single n-number perovskite phase for n  >  2 by mechanical exfoliation. Micro-photoluminescence and absorption spectroscopy studies reveal that the as-synthesized 2D perovskite plates for n  >  2 are comprised by dominant n-number phase and small inclusions of hybrid perovskite phases with different n values, which is supported by excitation power dependent photoluminescence. By mechanical exfoliation method, 2D perovskite microplates with the thickness of around 20 nm are obtained, which surprisingly have single n-number perovskite phase for n  =  2-5. In addition, we have demonstrated that the exfoliated 2D perovskite microplates can be integrated with other 2D layered materials such as boron nitride, and are able to be transferred to prefabricated electrodes for photodetections. Our studies not only provide a strategy to prepare 2D perovskites with a single n-number perovskite phase allowing us to extract the basic optical and electronic parameters of pure phase perovskites, but also demonstrate the possibility to integrate the 2D perovskites with other 2D layered materials to extend the device’s functionalities.

Akt2/ZEB2 may be a biomarker for exfoliant cells in ascitic fluid in advanced grades of serous ovarian carcinoma.

Science.gov (United States)

Liu, Changmei; Yang, Fangmei

2015-09-01

Ovarian cancers present a mild clinical course when diagnosed early but an aggressive pathway when diagnosed in the peri- and postmenopausal periods. However, the predictability of tumor progression is stochastic and is difficult to predict. In the present study, we hypothesized to examine the key pathways that are dysregulated to promote epithelial-mesenchymal transition in serous ovarian carcinoma. Examination of these steps would help to identify ascitic fluid with cells poised for metastasis or otherwise. We focused on examining the Akt2 expression, mainly because of its report as being overamplified in the aggressive variants of ovarian cancer, as well as TGFbeta-sensitivity of Akt2 that forms the key basis for metastasis initiation of most kinds of carcinoma. We obtained primary ovarian carcinoma samples as well as ascitic fluid and distantly metastatic ovarian carcinoma to examine the expression of Akt2. The results of the study demonstrated that in malignant exfoliated ovarian cancer cells, Smad4 expression was tremendously increased in the nuclei, suggesting nuclear translocation of Smad, which thereafter may have activated ZEB2, and thereafter genomically affected the expression of E-cadherin, myosin II, and vimentin, key components for initiating and sustaining metastasis. All of these may have been stimulated by increased cellular expression of Akt2 in metastatic variants of the serous ovarian carcinoma. The reliance on Akt2 and TGF beta signaling may also potentiate the case for Akt inhibitors or small molecule inhibitors of TGFbeta signaling like doxycycline as adjunct chemotherapy in serous ovarian carcinoma, especially the metastatic variants.

Elevated expression of NEU1 sialidase in idiopathic pulmonary fibrosis provokes pulmonary collagen deposition, lymphocytosis, and fibrosis.

Science.gov (United States)

Luzina, Irina G; Lockatell, Virginia; Hyun, Sang W; Kopach, Pavel; Kang, Phillip H; Noor, Zahid; Liu, Anguo; Lillehoj, Erik P; Lee, Chunsik; Miranda-Ribera, Alba; Todd, Nevins W; Goldblum, Simeon E; Atamas, Sergei P

2016-05-15

Idiopathic pulmonary fibrosis (IPF) poses challenges to understanding its underlying cellular and molecular mechanisms and the development of better therapies. Previous studies suggest a pathophysiological role for neuraminidase 1 (NEU1), an enzyme that removes terminal sialic acid from glycoproteins. We observed increased NEU1 expression in epithelial and endothelial cells, as well as fibroblasts, in the lungs of patients with IPF compared with healthy control lungs. Recombinant adenovirus-mediated gene delivery of NEU1 to cultured primary human cells elicited profound changes in cellular phenotypes. Small airway epithelial cell migration was impaired in wounding assays, whereas, in pulmonary microvascular endothelial cells, NEU1 overexpression strongly impacted global gene expression, increased T cell adhesion to endothelial monolayers, and disrupted endothelial capillary-like tube formation. NEU1 overexpression in fibroblasts provoked increased levels of collagen types I and III, substantial changes in global gene expression, and accelerated degradation of matrix metalloproteinase-14. Intratracheal instillation of NEU1 encoding, but not control adenovirus, induced lymphocyte accumulation in bronchoalveolar lavage samples and lung tissues and elevations of pulmonary transforming growth factor-β and collagen. The lymphocytes were predominantly T cells, with CD8(+) cells exceeding CD4(+) cells by nearly twofold. These combined data indicate that elevated NEU1 expression alters functional activities of distinct lung cell types in vitro and recapitulates lymphocytic infiltration and collagen accumulation in vivo, consistent with mechanisms implicated in lung fibrosis.

The clinical value of circulating tumour cells (CTCs) in patients undergoing pulmonary metastasectomy for metastatic colorectal cancer.

Science.gov (United States)

Hashimoto, Masaki; Tanaka, Fumihiro; Yoneda, Kazue; Takuwa, Teruhisa; Kuroda, Ayumi; Matsumoto, Seiji; Okumura, Yoshitomo; Kondo, Nobuyuki; Tsujimura, Tohru; Nakano, Takashi; Hasegawa, Seiki

2018-03-01

Circulating tumour cells (CTCs) are a potential surrogate for distant metastasis and are considered a useful clinical prognostic marker for metastatic colorectal cancer (mCRC). This prospective study evaluated the preoperative CTC count as a prognostic factor for pulmonary metastasectomy in mCRC patients. Seventy-nine mCRC patients who underwent curative-intent pulmonary metastasectomy were included. Preoperatively, 7.5 mL of peripheral blood from each patient was quantitatively evaluated for CTCs with the CellSearch ® system. The clinical significance of CTC count was evaluated according to Kaplan-Meier analyses and log-rank test. Multivariate analyses of the perioperative variables were performed. The distribution of CTC counts were as follows; 0 in 66 patients (83.5%), 1 in eight patients (10.1%), 2 in three patients (3.8%), and 3 and 6 in one patient (1.3%). The patients with multiple CTCs (CTC count ≥2) had significant shorter disease-free survival (DFS) (P=0.005, median DFS; 19.8 vs . 8.6 months) and overall survival (OS) (P=0.035, median DFS; not reached vs. 37.8 months), respectively. Multivariate analysis showed the patients with multiple CTCs had elevated risk of recurrence [hazard ratio (HR), 3.28; 95% confidence interval (CI), 1.24-8.67; P=0.017]. The detected rate of CTCs was quite low in mCRC patients who underwent pulmonary metastasectomy. The patient with multiple CTCs had shorter DFS in this study. The larger prospective clinical study is needed to establish the meaning of CTC in mCRC candidate for pulmonary metastasectomy.

Pulmonary langerhans cell histiocytosis in adults: high-resolution CT - pathology comparisons and evolutional changes at CT

Energy Technology Data Exchange (ETDEWEB)

Kim, Hyo Jin; Lee, Ho Yun; Kim, Tae Sung [Sungkyunkwan University School of Medicine, Department of Radiology and Center for Imaging Science, Samsung Medical Center, Seoul (Korea, Republic of); Lee, Kyung Soo [Sungkyunkwan University School of Medicine, Department of Radiology and Center for Imaging Science, Samsung Medical Center, Seoul (Korea, Republic of); Samsung Medical Center, Department of Radiology, Seoul (Korea, Republic of); Johkoh, Takeshi [Kinki Central Hospital of Mutual Aid Association of Public School Teachers, Department of Radiology, Hyoko (Japan); Tomiyama, Noriyuki [Osaka University Graduate School of Medicine, Department of Radiology, Osaka (Japan); Han, Joungho [Sungkyunkwan University School of Medicine, Department of Pathology, Samsung Medical Center, Seoul (Korea, Republic of)

2011-07-15

To compare high-resolution (HR) CT and histopathological findings and to evaluate serial CT findings in pulmonary Langerhans cell histiocytosis (PLCH). We reviewed CT of lung lesions in 27 adults (M:F = 20:7, mean age, 41 {+-} 12.3 years) with PLCH. After evaluating lung abnormalities including nodules, micronodules, thick-walled, thin-walled, and bizarre-shaped cysts and reticulation, observers compared CT findings obtained at lung biopsy sites with histopathological findings. The final CT was compared with the initial CT to determine disease extent changes. The most frequently observed patterns of lung abnormalities were micronodules (n = 24, 89%), thick-walled (n = 22, 82%), and thin-walled (n = 22, 82%) cysts. Even thin-walled and bizarre cysts harboured active inflammatory Langerhans cell sheets and eosinophils in their walls. In thin-walled cysts, we noted pericystic inflammatory cell infiltrations along the alveolar walls, as well as pericystic emphysema. Thin-walled or bizarre cysts demonstrated a tendency to coalesce with surrounding cysts via their cystic wall destruction. Fourteen (52%) patients showed improvement and nine (33%) showed progressing disease. More than half of patients with pulmonary PLCH show improvement at follow-up CT. Even thin-walled cysts harbour active inflammatory cells on histopathology and exhibit improvement at follow-up CT. (orig.)

Single-layered graphene oxide nanosheet/polyaniline hybrids fabricated through direct molecular exfoliation.

Science.gov (United States)

Chen, Guan-Liang; Shau, Shi-Min; Juang, Tzong-Yuan; Lee, Rong-Ho; Chen, Chih-Ping; Suen, Shing-Yi; Jeng, Ru-Jong

2011-12-06

In this study, we used direct molecular exfoliation for the rapid, facile, large-scale fabrication of single-layered graphene oxide nanosheets (GOSs). Using macromolecular polyaniline (PANI) as a layered space enlarger, we readily and rapidly synthesized individual GOSs at room temperature through the in situ polymerization of aniline on the 2D GOS platform. The chemically modified GOS platelets formed unique 2D-layered GOS/PANI hybrids, with the PANI nanorods embedded between the GO interlayers and extended over the GO surface. X-ray diffraction revealed that intergallery expansion occurred in the GO basal spacing after the PANI nanorods had anchored and grown onto the surface of the GO layer. Transparent folding GOSs were, therefore, observed in transmission electron microscopy images. GOS/PANI nanohybrids possessing high conductivities and large work functions have the potential for application as electrode materials in optoelectronic devices. Our dispersion/exfoliation methodology is a facile means of preparing individual GOS platelets with high throughput, potentially expanding the applicability of nanographene oxide materials. © 2011 American Chemical Society

Picfeltarraenin IA inhibits lipopolysaccharide-induced inflammatory cytokine production by the nuclear factor-κB pathway in human pulmonary epithelial A549 cells.

Science.gov (United States)

Shi, Rong; Wang, Qing; Ouyang, Yang; Wang, Qian; Xiong, Xudong

2016-02-01

The present study aimed to investigate the effect of picfeltarraenin IA (IA) on respiratory inflammation by analyzing its effect on interleukin (IL)-8 and prostaglandin E2 (PGE2) production. The expression of cyclooxygenase 2 (COX2) in human pulmonary adenocarcinoma epithelial A549 cells in culture was also examined. Human pulmonary epithelial A549 cells and the human monocytic leukemia THP-1 cell line were used in the current study. Cell viability was measured using a methylthiazol tetrazolium assay. The production of IL-8 and PGE2 was investigated using an enzyme-linked immunosorbent assay. The expression of COX2 and nuclear factor-κB (NF-κB)-p65 was examined using western blot analysis. Treatment with lipopolysaccharide (LPS; 10 µg/ml) resulted in the increased production of IL-8 and PGE2, and the increased expression of COX2 in the A549 cells. Furthermore, IA (0.1-10 µmol/l) significantly inhibited PGE2 production and COX2 expression in cells with LPS-induced IL-8, in a concentration-dependent manner. The results suggested that IA downregulates LPS-induced COX2 expression, and inhibits IL-8 and PGE2 production in pulmonary epithelial cells. Additionally, IA was observed to suppress the expression of COX2 in THP-1 cells, and also to regulate the expression of COX2 via the NF-κB pathway in the A549 cells, but not in the THP-1 cells. These results indicate that IA regulates LPS-induced cytokine release in A549 cells via the NF-κB pathway.

Covalent modification and exfoliation of graphene oxide using ferrocene

Science.gov (United States)

Avinash, M. B.; Subrahmanyam, K. S.; Sundarayya, Y.; Govindaraju, T.

2010-09-01

Large scale preparation of single-layer graphene and graphene oxide is of great importance due to their potential applications. We report a simple room temperature method for the exfoliation of graphene oxide using covalent modification of graphene oxide with ferrocene to obtain single-layer graphene oxide sheets. The samples were characterized by FESEM, HRTEM, AFM, EDAX, FT-IR, Raman and Mössbauer spectroscopic studies. HRTEM micrograph of the covalently modified graphene oxide showed increased interlayer spacing of ~2.4 nm due to ferrocene intercalation. The presence of single-layer graphene oxide sheets were confirmed by AFM studies. The covalently modified ferrocene-graphene oxide composite showed interesting magnetic behavior.Large scale preparation of single-layer graphene and graphene oxide is of great importance due to their potential applications. We report a simple room temperature method for the exfoliation of graphene oxide using covalent modification of graphene oxide with ferrocene to obtain single-layer graphene oxide sheets. The samples were characterized by FESEM, HRTEM, AFM, EDAX, FT-IR, Raman and Mössbauer spectroscopic studies. HRTEM micrograph of the covalently modified graphene oxide showed increased interlayer spacing of ~2.4 nm due to ferrocene intercalation. The presence of single-layer graphene oxide sheets were confirmed by AFM studies. The covalently modified ferrocene-graphene oxide composite showed interesting magnetic behavior. Electronic supplementary information (ESI) available: Magnetic data; AFM images; TEM micrographs; and Mössbauer spectroscopic data. See DOI: 10.1039/c0nr00024h

miR-143 Activation Regulates Smooth Muscle and Endothelial Cell Crosstalk in Pulmonary Arterial Hypertension

Science.gov (United States)

Stevens, Hannah; Lu, Ruifang; Caudrillier, Axelle; McBride, Martin; McClure, John D; Grant, Jenny; Thomas, Matthew; Frid, Maria; Stenmark, Kurt; White, Kevin; Seto, Anita G.; Morrell, Nicholas W.; Bradshaw, Angela C; MacLean, Margaret R.; Baker, Andrew H.

2015-01-01

Rationale The pathogenesis of PAH remains unclear. The four microRNAs representing the miR-143 and miR-145 stem loops are genomically clustered. Objective To elucidate the transcriptional regulation of the miR-143/145 cluster, and the role of miR-143 in PAH. Methods and Results We identified the promoter region that regulates miR-143/145 miRNA expression in pulmonary artery smooth muscle cells (PASMCs). We mapped PAH-related signalling pathways, including estrogens receptor (ER), liver X factor/retinoic X receptor (LXR/RXR), TGF-β (Smads), and hypoxia (HRE) that regulated levels of all pri-miR stem loop transcription and resulting miRNA expression. We observed that miR-143-3p is selectively upregulated compared to miR-143-5p during PASMC migration. Modulation of miR-143 in PASMCs significantly altered cell migration and apoptosis. In addition, we found high abundance of miR-143-3p in PASMCs-derived exosomes. Using assays with pulmonary arterial endothelial cells (PAECs) we demonstrated a paracrine pro-migratory and pro-angiogenic effect of miR-143-3p enriched exosomes from PASMC. Quantitative PCR and in situ hybridisation showed elevated expression of miR-143 in calf models of PAH as well as in samples from PAH patients. Moreover, in contrast to our previous findings that had not supported a therapeutic role in vivo, we now demonstrate a protective role for miR-143 in experimental PH in vivo in miR-143−/− and antimiR143-3p-treated mice exposed to chronic hypoxia in both preventative and reversal settings. Conclusions miR-143-3p modulated both cellular and exosome-mediated responses in pulmonary vascular cells, while inhibition of miR-143-3p blocked experimental PH. Taken together these findings confirm an important role for the miR-143/145 cluster in PAH pathobiology. PMID:26311719

Electrochemical performance of 3D porous Ni-Co oxide with electrochemically exfoliated graphene for asymmetric supercapacitor applications

International Nuclear Information System (INIS)

Kim, Dae Kyom; Hwang, Minsik; Ko, Dongjin; Kang, Jeongmin; Seong, Kwang-dong; Piao, Yuanzhe

2017-01-01

Graphical abstract: The paper reported the Ni-Co oxide/electrochemically exfoliated graphene nanocomposites with 3D porous nano-architectures (NC-EEG) using a simple low temperature solution method combined with a thermal annealing treatment. 3D porous architectures provide large surface areas and shorten electron diffusion pathways for high performance asymmetric supercapacitors. Display Omitted -- Highlights: •A simple low temperature solution method was used for preparing NC-EEG. •Graphene sheets were obtained by electrochemically exfoliation process. •A high capacity of NC-EEG in a three-electrode system, as high as 649 C g −1 , was recorded. •Asymmetric supercapacitor based on NC-EEG exhibited excellent energy density and power density. -- Abstract: Ni-Co oxide, one of the binary metal oxides, has many advantages for use in high-performance supercapacitor electrode materials due to its relatively high electronic conductivity and improved electrochemical performance. In this work, Ni-Co oxide/electrochemically exfoliated graphene nanocomposites (NC-EEG) are successfully synthesized using a simple low temperature solution method combined with a thermal annealing treatment. Graphene sheets are directly obtained by an electrochemical exfoliation process with graphite foil, which is very simple, environmentally friendly, and has a relatively short reaction time. This electrochemically exfoliated graphene (EEG) can improve the electrical conductivity of the Ni-Co oxide nanostructures. The as-prepared NC-EEG nanocomposites have 3D porous architectures that can provide large surface areas and shorten electron diffusion pathways. Electrochemical properties were performed by cyclic voltammetry and galvanostatic charge/discharge in a 6 M KOH electrolyte. The NC-EEG nanocomposites exhibited a high capacity value of 649 C g −1 at a current density of 1.0 A g −1 . The asymmetric supercapacitors, manufactured on the basis of NC-EEG nanocomposites as a positive

Chemically exfoliated Mo S2 layers: Spectroscopic evidence for the semiconducting nature of the dominant trigonal metastable phase

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Pal, Banabir; Singh, Anjali; Sharada, G.; Mahale, Pratibha; Kumar, Abhinav; Thirupathaiah, S.; Sezen, H.; Amati, M.; Gregoratti, Luca; Waghmare, Umesh V.; Sarma, D. D.

2017-11-01

A metastable trigonal phase, existing only as small patches on a chemically exfoliated few-layered, thermodynamically stable 1 H phase of Mo S2 , is believed to critically influence the properties of Mo S2 -based devices. The electronic structure of this metastable phase is little understood in the absence of a direct experimental investigation of its electronic properties, complicated further by conflicting claims from theoretical investigations. We address this issue by investigating the electronic structure of this minority phase in chemically exfoliated Mo S2 few-layered systems by enhancing its contributions with the use of highly spatially resolved (≤120 nm resolution) photoemission spectroscopy and Raman spectroscopy in conjunction with state-of-the-art electronic structure calculations. Based on these results, we establish that the ground state of this phase, arrived at by the chemical exfoliation of Mo S2 using the usual Li intercalation technique, is a small gap (˜90 ±40 meV ) semiconductor in contrast to most claims in the literature; we also identify the specific trigonal structure it has among many suggested ones.

Genotoxic effects of silver amalgam and composite restorations: Micronuclei-Based cohort and case–control study in oral exfoliated cells

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S Jeslin Mary

2018-01-01

Full Text Available Context: A huge number of people carry dental fillings which contain either mercury-based amalgam and/or the recently introduced methacrylate-based resins. It has been shown that both these materials are known to be leached into the oral cavity and induce genotoxic alterations in the buccal mucosal cells. Because of its low cost and ease of manipulation, dental amalgam is still widely used as a restorative material in developing countries. The health risks associated with the components of this restorative material has always been a matter of concern. The present study was designed to assess the frequency of micronuclei (MN in oral mucosal cells as it is a promising tool for studying the genotoxic effect of clastogenic agents on them. Aims: The aim of this study is to evaluate the genotoxic effects of silver amalgam and composite restorations by measuring the mean number of MN in oral exfoliated cells. Materials and Methods: The present study was a prospective cohort study which includes a study group consisting of 110 participants. The study sample was equally divided into 55 participants requiring only amalgam restoration and 55 participants requiring only composite restoration in any permanent molar teeth. The same participants before the restoration formed the control group. Smears were obtained from each patient before and 10 days after restoration and were stained with DNA-specific Feulgen stain. The number of cells containing MN out of 500 cells were counted and recorded. After the evaluation of the slides, the results were compiled and subjected to statistical analysis. Results: There was a statistically significant (P < 0.01 variation in the mean number of MN after the restoration in both amalgam (5.41 ± 1.25 and composite (2.83 ± 0.85 restorations when compared to before the restoration. However, the mean number of MN in composite restoration was significantly less when compared to amalgam restoration. There was also a statistically

Prognostic Significance of BMI-1 But Not MEL-18 Expression in Pulmonary Squamous Cell Carcinoma.

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Abe, Sosei; Yamashita, Shin-Ichi; Miyahara, S O; Wakahara, Junichi; Yamamoto, Leona; Mori, Ryo; Imamura, Naoko; Yoshida, Yasuhiro; Waseda, Ryuichi; Hiratsuka, Masafumi; Shiraishi, Takeshi; Nabeshima, Kazuki; Iwasaki, Akinori

2017-04-01

We investigated the possibility of BMI-1 and MEL-18 to predict survival in patients with pulmonary squamous cell carcinoma. One hundred and ninety-nine patients underwent surgery in our Institute between 1995 and 2005. We used immunohistochemical (IHC) analysis to determine the expressions of BMI-1 and MEL-18 and compared them with clinicopathological factors and survival. Forty-one of 199 cases (21%) were BMI-1-positive. No correlation was found between BMI-1 and MEL-18 expression by IHC and clinicopathological factors. Five-year overall survival in the BMI-1-positive group (66.8%), but not MEL-18, was significantly better than that in the negative group (45.5%, p=0.04). In multivariate analysis, positive BMI-1 was a better prognostic factor of overall survival (hazard ratio (HR)=0.561, 95% confidence interval (CI)=0.271-1.16, p=0.12). BMI-1 expression, but not MEL-18, is associated with a favorable prognosis and is a possible prognostic factor of pulmonary squamous cell carcinoma. Copyright© 2017, International Institute of Anticancer Research (Dr. George J. Delinasios), All rights reserved.

Adrenomedullin and adrenotensin regulate collagen synthesis and proliferation in pulmonary arterial smooth muscle cells

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Li, W. [School of Control Science and Engineering, Biomedical Engineering Institute, Shandong University, Jinan, Shandong (China); Kong, Q.Y.; Zhao, C.F. [Department of Pediatrics, Qilu Hospital, Shandong University, Jinan, Shandong (China); Zhao, F. [Department of Medicine, Weill Medical College of Cornell University, New York, NY (United States); Li, F.H.; Xia, W. [Department of Pediatrics, Qilu Hospital, Shandong University, Jinan, Shandong (China); Wang, R. [Key Laboratory of Cardiovascular Remodeling and Function Research, Qilu Hospital, Shandong University, Jinan, Shandong (China); Hu, Y.M. [School of Control Science and Engineering, Biomedical Engineering Institute, Shandong University, Jinan, Shandong (China); Hua, M. [Shandong Institute of Scientific and Technical Information, Jinan, Shandong (China)

2013-12-10

To understand the pathophysiological mechanisms of pulmonary arterial smooth muscle cell (PASMC) proliferation and extracellular-matrix accumulation in the development of pulmonary hypertension and remodeling, this study determined the effects of different doses of adrenomedullin (ADM) and adrenotensin (ADT) on PASMC proliferation and collagen synthesis. The objective was to investigate whether extracellular signal-regulated kinase (ERK1/2) signaling was involved in ADM- and ADT-stimulated proliferation of PASMCs in 4-week-old male Wistar rats (body weight: 100-150 g, n=10). The proliferation of PASMCs was examined by 5-bromo-2-deoxyuridine incorporation. A cell growth curve was generated by the Cell Counting Kit-8 method. Expression of collagen I, collagen III, and phosphorylated ERK1/2 (p-ERK1/2) was evaluated by immunofluorescence. The effects of different concentrations of ADM and ADT on collagen I, collagen III, and p-ERK1/2 protein expression were determined by immunoblotting. We also investigated the effect of PD98059 inhibition on the expression of p-ERK1/2 protein by immunoblotting. ADM dose-dependently decreased cell proliferation, whereas ADT dose-dependently increased it; and ADM and ADT inhibited each other with respect to their effects on the proliferation of PASMCs. Consistent with these results, the expression of collagen I, collagen III, and p-ERK1/2 in rat PASMCs decreased after exposure to ADM but was upregulated after exposure to ADT. PD98059 significantly inhibited the downregulation by ADM and the upregulation by ADT of p-ERK1/2 expression. We conclude that ADM inhibited, and ADT stimulated, ERK1/2 signaling in rat PASMCs to regulate cell proliferation and collagen expression.

RADIOAUTOGRAPHIC DEMONSTRATION OF 5-HYDROXYTRYPTAMINE-3H UPTAKE BY PULMONARY ENDOTHELIAL CELLS

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Strum, Judy M.; Junod, Alain F.

1972-01-01

The lung is able to rapidly remove 5-hydroxytryptamme (5-HT) from the circulation by a Na+-dependent transport mechanism. In order to identify the sites of uptake, radioautographic studies were done on rat lungs which had been isolated and perfused with 5-HT-3H and 0 5 mM iproniazid, a monoamine oxidase inhibitor. In control experiments 10-4 M imipramine was added to the perfusate to inhibit the membrane transport of 5-HT At the light microscope level, silver grains were seen concentrated near capillaries and in the endothelium of large vessels From electron microscope radioautographs a semiquantitative grain count was made and 90% of the silver grains were observed over capillary endothelial cells. The grains were found over the nucleus and cytoplasm of the cell and shewed no preferential association with any particular cytoplasmic inclusion bodies, organelles, or vesicles Other cell types were unlabeled except for a few mast cells, certain vascular smooth muscle cells, and one nerve ending. This radioautographic demonstration of the cell type responsible for the rapid removal of 5-HT from the lung circulation clearly establishes the existence of a new metabolic role for pulmonary endothelial cells. PMID:5044755

Pulmonary Langerhans Cell Histiocytosis with Lytic Bone Involvement in an Adult Smoker: Regression following Smoking Cessation

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B. Routy

2015-01-01

Full Text Available Langerhans cell histiocytosis (LCH is a rare myeloid neoplasm characterized by the proliferation and dissemination of histiocytes. These in turn may cause symptoms ranging from isolated, infiltrative lesions to severe multisystem disease. Pulmonary Langerhans cell histiocytosis (PLCH presents as a localized polyclonal proliferation of Langerhans cells in the lungs causing bilateral cysts and fibrosis. In adults, this rare condition is considered a reactive process associated with cigarette smoking. Recently, clonal proliferation has been reported with the presence of BRAF V600E oncogenic mutation in a subset of PLCH patients. Spontaneous resolution was described; however, based on case series, smoking cessation remains the most effective way to achieve complete remission and prevent long term complications related to tobacco. Herein, we report the case of an adult woman with biopsy-proven PLCH presenting with thoracic (T8 vertebral bone destruction. Both the lung and the bone diseases regressed following smoking cessation, representing a rare case of synchronous disseminated PCLH with bone localization. This observation underscores the contribution of cigarette smoking as a systemic trigger of both pulmonary and extrapulmonary bone lesions. A review of similar cases in the literature is also presented.

Defective pulmonary innate immune responses post-stem cell transplantation; review and results from one model system

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Racquel eDomingo-Gonzalez

2013-05-01

Full Text Available Infectious pulmonary complications limit the success of hematopoietic stem cell transplantation (HSCT as a therapy for malignant and nonmalignant disorders. Susceptibility to pathogens in both autologous and allogeneic HSCT recipients persists despite successful immune reconstitution. As studying the causal effects of these immune defects in the human population can be limiting, a bone marrow transplant (BMT mouse model can be used to understand the defect in mounting a productive innate immune response post-transplantation. When syngeneic BMT is performed, this system allows the study of BMT-induced alterations in innate immune cell function that are independent of the confounding effects of immunosuppressive therapy and graft-versus-host disease. Studies from several laboratories, including our own show that pulmonary susceptibility to bacterial infections post-BMT are largely due to alterations in the lung alveolar macrophages. Changes in these cells post-BMT include cytokine and eicosanoid dysregulations, scavenger receptor alterations, changes in micro RNA profiles, and alterations in intracellular signaling molecules that limit bacterial phagocytosis and killing. The changes that occur highlight mechanisms that promote susceptibility to infections commonly afflicting HSCT recipients and provide insight into therapeutic targets that may improve patient outcomes post-HSCT.

Radiotherapy and pulmonary fibrosis

Energy Technology Data Exchange (ETDEWEB)

Sone, S; Miyata, Y; Tachiiri, H [Osaka Univ. (Japan). Faculty of Medicine

1975-04-01

Clinical findings of radiation pneumonitis and pulmonary fibrosis were outlined, and the relationship between occurence of these disorders and radiotherapy, clinical findings and X-ray picture were studied. Standard radiation dose as cell lethal response of carcinoma of the lung were 4,500 to 5,500 rad in 4 to 5.5 weeks in undifferentiated carcinoma, 6,000 to 7,000 rad in 6 to 7 weeks in squamous cell carcinoma, 7,000 to 9,000 rad in 7 to 9 weeks in adenocarcinoma, 4,500 to 5,000 rad in 4 to 5 weeks in the large sized cancer of the esophagus, 6,500 to 7,000 rad in 5 to 7 weeks in the small sized cancer of the esophagus, and irradiation of these amount of dose caused hazards in pulmonary function. Pathological and clinical findings of pulmonary hazards within 6 month period after irradiation, factors causing them and changes in X-ray pictures before and after irradiation were observed and discussed in clinical cases: the case of breast cancer in which 3,000 R/6 times/18 days of 5.5 MeV Liniac electron was irradiated to the chest wall, and the case of pulmonary cancer in which 5,000 rad/25 times/34 days of 6 MeV Liniac X-ray was irradiated in opposite 2 ports radiation beam treatment. The former revealed alveolar lesion and interlobular pleuritis at 4 month later, and remarkable lesion of pulmonary fibrosis was followed at 9 month after radiotherapy. The later developed radiation pneumonitis 1 month after radiotherapy, of which lesion extended to the upper part by 3 months later, and cancer recurred 6.5 month later.

Differential pulmonary and cardiac effects of pulmonary exposure to a panel of particulate matter-associated metals

International Nuclear Information System (INIS)

Wallenborn, J. Grace; Schladweiler, Mette J.; Richards, Judy H.; Kodavanti, Urmila P.

2009-01-01

Biological mechanisms underlying the association between particulate matter (PM) exposure and increased cardiovascular health effects are under investigation. Water-soluble metals reaching systemic circulation following pulmonary exposure are likely exerting a direct effect. However, it is unclear whether specific PM-associated metals may be driving this. We hypothesized that exposure to equimolar amounts of five individual PM-associated metals would cause differential pulmonary and cardiac effects. We exposed male WKY rats (14 weeks old) via a single intratracheal instillation (IT) to saline or 1 μmol/kg body weight of zinc, nickel, vanadium, copper, or iron in sulfate form. Responses were analyzed 4, 24, 48, or 96 h after exposure. Pulmonary effects were assessed by bronchoalveolar lavage fluid levels of total cells, macrophages, neutrophils, protein, albumin, and activities of lactate dehydrogenase, γ-glutamyl transferase, and n-acetyl glucosaminidase. Copper induced earlier pulmonary injury/inflammation, while zinc and nickel produced later effects. Vanadium or iron exposure induced minimal pulmonary injury/inflammation. Zinc, nickel, or copper increased serum cholesterol, red blood cells, and white blood cells at different time points. IT of nickel and copper increased expression of metallothionein-1 (MT-1) in the lung. Zinc, nickel, vanadium, and iron increased hepatic MT-1 expression. No significant changes in zinc transporter-1 (ZnT-1) expression were noted in the lung or liver; however, zinc increased cardiac ZnT-1 at 24 h, indicating a possible zinc-specific cardiac effect. Nickel exposure induced an increase in cardiac ferritin 96 h after IT. This data set demonstrating metal-specific cardiotoxicity is important in linking metal-enriched anthropogenic PM sources with adverse health effects.

Sustained hypoxia leads to the emergence of cells with enhanced growth, migratory, and promitogenic potentials within the distal pulmonary artery wall.

Science.gov (United States)

Frid, Maria G; Li, Min; Gnanasekharan, Meena; Burke, Danielle L; Fragoso, Miguel; Strassheim, Derek; Sylman, Joanna L; Stenmark, Kurt R

2009-12-01

All forms of chronic pulmonary hypertension (PH) are characterized by structural remodeling of the pulmonary artery (PA) media, a process previously attributed solely to changes in the phenotype of resident smooth muscle cells (SMC). However, recent experimental evidence in both systemic and pulmonary circulations suggests that other cell types, including circulating and local progenitors, contribute significantly to this process. The goal of this study was to determine if hypoxia-induced remodeling of distal PA (dPA) media involves the emergence of cells with phenotypic and functional characteristics distinct from those of resident dPA SMC and fibroblasts. In vivo, in contrast to the phenotypically uniform SMC composition of dPA media in control calves, the remodeled dPA media of neonatal calves with severe hypoxia-induced PH comprised cells exhibiting a distinct phenotype, including the expression of hematopoetic (CD45), leukocytic/monocytic (CD11b, CD14), progenitor (cKit), and motility-associated (S100A4) cell markers. Consistent with these in vivo observations, primary cell cultures isolated from dPA media of hypertensive calves yielded not only differentiated SMC, but also smaller, morphologically rhomboidal (thus termed here "R") cells that transiently expressed CD11b, constitutively expressed the mesenchymal cell marker type I procollagen, expressed high mRNA levels of progenitor cell markers cKit, CD34, CD73, as well as for inflammatory mediators, IL-6 and MCP-1, and, with time in culture, gained expression of a myofibroblast marker, alpha-SM-actin. R cells exhibited highly augmented proliferative, migratory, invasive, and potent promitogenic capabilities, which were due, at least in part, to the production of PDGFs, SDF-1/CXCL12, and S100A4. These data suggest that the cellular mechanisms of dPA remodeling include the emergence of cells with phenotypic and functional characteristics markedly distinct from those of resident dPA cells.

Chymase: a multifunctional player in pulmonary hypertension associated with lung fibrosis.

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Kosanovic, Djuro; Luitel, Himal; Dahal, Bhola Kumar; Cornitescu, Teodora; Janssen, Wiebke; Danser, A H Jan; Garrelds, Ingrid M; De Mey, Jo G R; Fazzi, Gregorio; Schiffers, Paul; Iglarz, Marc; Fischli, Walter; Ghofrani, Hossein Ardeschir; Weissmann, Norbert; Grimminger, Friedrich; Seeger, Werner; Reiss, Irwin; Schermuly, Ralph Theo

2015-10-01

Limited literature sources implicate mast-cell mediator chymase in the pathologies of pulmonary hypertension and pulmonary fibrosis. However, there is no evidence on the contribution of chymase to the development of pulmonary hypertension associated with lung fibrosis, which is an important medical condition linked with increased mortality of patients who already suffer from a life-threatening interstitial lung disease.The aim of this study was to investigate the role of chymase in this particular pulmonary hypertension form, by using a bleomycin-induced pulmonary hypertension model.Chymase inhibition resulted in attenuation of pulmonary hypertension and pulmonary fibrosis, as evident from improved haemodynamics, decreased right ventricular remodelling/hypertrophy, pulmonary vascular remodelling and lung fibrosis. These beneficial effects were associated with a strong tendency of reduction in mast cell number and activity, and significantly diminished chymase expression levels. Mechanistically, chymase inhibition led to attenuation of transforming growth factor β1 and matrix-metalloproteinase-2 contents in the lungs. Furthermore, chymase inhibition prevented big endothelin-1-induced vasoconstriction of the pulmonary arteries.Therefore, chymase plays a role in the pathogenesis of pulmonary hypertension associated with pulmonary fibrosis and may represent a promising therapeutic target. In addition, this study may provide valuable insights on the contribution of chymase in the pulmonary hypertension context, in general, regardless of the pulmonary hypertension form. Copyright ©ERS 2015.

Pulmonary Hypertension and Pulmonary Vasodilators.

Science.gov (United States)

Keller, Roberta L

2016-03-01

Pulmonary hypertension in the perinatal period can present acutely (persistent pulmonary hypertension of the newborn) or chronically. Clinical and echocardiographic diagnosis of acute pulmonary hypertension is well accepted but there are no broadly validated criteria for echocardiographic diagnosis of pulmonary hypertension later in the clinical course, although there are significant populations of infants with lung disease at risk for this diagnosis. Contributing cardiovascular comorbidities are common in infants with pulmonary hypertension and lung disease. It is not clear who should be treated without confirmation of pulmonary vascular disease by cardiac catheterization, with concurrent evaluation of any contributing cardiovascular comorbidities. Copyright © 2016 Elsevier Inc. All rights reserved.

Surfactant mediated liquid phase exfoliation of graphene

Science.gov (United States)

Narayan, Rekha; Kim, Sang Ouk

2015-10-01

Commercialization of graphene based applications inevitably requires cost effective mass production. From the early days of research on graphene, direct liquid phase exfoliation (LPE) of graphite has been considered as the most promising strategy to produce high-quality mono or few-layer graphene sheets in solvent dispersion forms. Substantial success has been achieved thus far in the LPE of graphene employing numerous solvent systems and suitable surfactants. This invited review article principally showcase the recent research progress as well as shortcomings of surfactant assisted LPE of graphene. In particular, a comprehensive assessment of the quality and yield of the graphene sheets produced by different categories of the surfactants are summarized. Future direction of LPE methods is also proposed for the eventual success of commercial applications.

The Prognosis of Small Cell Lung Cancer in Patients with Pulmonary Fibrosis.

Science.gov (United States)

Matsumoto, Yoko; Ohara, Sayaka; Furukawa, Ryutaro; Usui, Kazuhiro

2017-10-01

The purpose of this study was to assess the prognosis of small cell lung cancer (SCLC) based on the underlying pulmonary disease. A total of 204 patients with SCLC were reviewed and categorized into three groups: normal, emphysema and fibrosis. The median overall survival duration (OS) in patients with normal lungs (n=57), with emphysema (n=105) and fibrosis (n=42) was 21.3, 16.4 and 10.8 months (p=0.063). In limited-stage disease (LD), the median OS in patients with fibrosis (7.4 months) was shorter than normal (52.7 months) or emphysema patients (26.4 months) (p=0.034). In extensive-stage disease (ED), the median OS in patients with fibrosis (12.7 months) was not significantly different from normal (11.4 months) or emphysema patients (13.5 months) (p=0.600). Patients with fibrosis had a poorer prognosis than normal or emphysema patients in LD-SCLC, but the coexistence of pulmonary fibrosis did not affect the prognostic outcomes in ED-SCLC. Copyright© 2017, International Institute of Anticancer Research (Dr. George J. Delinasios), All rights reserved.

A protocol proposition of cell therapy for the treatment of chronic obstructive pulmonary disease.

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Ribeiro-Paes, J T; Stessuk, T; Marcelino, M; Faria, C; Marinelli, T; Ribeiro-Paes, M J

2014-01-01

The main feature of pulmonary emphysema is airflow obstruction resulting from the destruction of the alveolar walls distal to the terminal bronchioles. Existing clinical approaches have improved and extended the quality of life of emphysema patients. However, no treatment currently exists that can change the disease course and cure the patient. The different therapeutic approaches that are available aim to increase survival and/or enhance the quality of life of emphysema patients. In this context, cell therapy is a promising therapeutic approach with great potential for degenerative pulmonary diseases. In this protocol proposition, all patients will be submitted to laboratory tests, such as evaluation of heart and lung function and routine examinations. Stem cells will be harvested by means of 10 punctures on each anterior iliac crest, collecting a total volume of 200mL bone marrow. After preparation, separation, counting and labeling (optional) of the mononuclear cells, the patients will receive an intravenous infusion from the pool of Bone Marrow Mononuclear Cells (BMMC). This article proposes a rational and safe clinical cellular therapy protocol which has the potential for developing new projects and can serve as a methodological reference for formulating clinical application protocols related to the use of cellular therapy in COPD. This study protocol was submitted and approved by the Brazilian National Committee of Ethics in Research (CONEP - Brazil) registration number 14764. It is also registered in ClinicalTrials.gov (NCT01110252). Copyright © 2013 Sociedade Portuguesa de Pneumologia. Published by Elsevier España. All rights reserved.

Pulmonary Arterial Stiffness: Toward a New Paradigm in Pulmonary Arterial Hypertension Pathophysiology and Assessment.

Science.gov (United States)

Schäfer, Michal; Myers, Cynthia; Brown, R Dale; Frid, Maria G; Tan, Wei; Hunter, Kendall; Stenmark, Kurt R

2016-01-01